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BJH324JH
11-16-2021, 07:49 AM
I'm currently having an engine shop do a rebuild for my 1988 mighty max and they told me the cylinder head is cracked. Do you happen to know if I should repair it or just replace it? I found a cylinder head on rockauto, but there is two choices to pick from. I don't know which one to choose. How do I know which is the correct head for my truck? It's a G54B engine. 26960

Also, any tips about the G54B engine rebuilding process I should let the engine shop know?

BJH324JH
11-16-2021, 11:06 AM
I'm currently having an engine shop do a rebuild for my 1988 mighty max and they told me the cylinder head is cracked. Do you happen to know if I should repair it or just replace it? I found a cylinder head on rockauto, but there is two choices to pick from. I don't know which one to choose. How do I know which is the correct head for my truck? It's a G54B engine. 26960

Also, any tips about the G54B engine rebuilding process I should let the engine shop know?

What do you guys think of this cylinder head?:
https://www.ebay.com/itm/164247587066

Has mechanical lifters rather than hydraulic. I was told on the phone that mechanical lifters are much better than hydraulic lifters. The guy told me they would just have to be adjusted after 30,000 miles. He told me the head is cast in China with no jet valve ports. He said everything else on the cylinder head is made in the U.S.A, out in Vegas. From the little research I did, jet valves seem to Crack the cylinder head. So, that's why the majority of people dislike them.
https://www.ebay.com/itm/164247587066

geezer101
11-16-2021, 12:44 PM
Mechanical is the way to go. Jet valves can also burn out. It's not so much the jet valves crack the head but the threaded hole into the combustion chamber creates a weak point in the casting. The constant expanding and contracting of the steel jet valve body in the die cast alloy leads to the alloy getting stressed and if you're unlucky for those heat cycles to be excessive, it'll crack through where there is the least amount of alloy in the combustion chamber between recesses/holes.

*new head - always do a leak down test on a bench. Make sure all the valves are seating properly before it gets installed. There are some garbage heads on the market and some of the worst culprits are after market performance heads for V8's. Port match the intake to the head. Nothing nuts, just a small ramp/taper on the intake port entrances to the head to tidy it up. It will help improve intake air/fuel charge velocity.

**addendum - don't go 'by the book' to set lifter clearances. It'll rattle like a typewriter. My experience is get the engine up to operating temps and adjust them by feel. It takes a little practice but once they're set, they won't need to be touched for a long time. It will run quieter and you'll get full advantage of valve lift which = power.

BJH324JH
11-16-2021, 01:43 PM
Mechanical is the way to go. Jet valves can also burn out. It's not so much the jet valves crack the head but the threaded hole into the combustion chamber creates a weak point in the casting. The constant expanding and contracting of the steel jet valve body in the die cast alloy leads to the alloy getting stressed and if you're unlucky for those heat cycles to be excessive, it'll crack through where there is the least amount of alloy in the combustion chamber between recesses/holes.

*new head - always do a leak down test on a bench. Make sure all the valves are seating properly before it gets installed. There are some garbage heads on the market and some of the worst culprits are after market performance heads for V8's. Port match the intake to the head. Nothing nuts, just a small ramp/taper on the intake port entrances to the head to tidy it up. It will help improve intake air/fuel charge velocity.

**addendum - don't go 'by the book' to set lifter clearances. It'll rattle like a typewriter. My experience is get the engine up to operating temps and adjust them by feel. It takes a little practice but once they're set, they won't need to be touched for a long time. It will run quieter and you'll get full advantage of valve lift which = power.

Thank you so much for the valuable information. I'm glad you are still active on the forum. It's been a while since I've been here. Also, what's the chance of the cast iron block to be cracked as well?

geezer101
11-16-2021, 10:28 PM
Not common, but it does happen. Mostly on the face of the block deck around the head bolt holes. It might be more the Conquest/Starquest/Starion engines due to boost or overtorqued bolts(?) Another place the blocks have been known to crack is the exhaust side of the block between the freeze plugs (this is on early Astron I 2.6 blocks) Generally the 2.6 block is a tough chunk of metal...

BJH324JH
11-22-2021, 03:15 PM
Not common, but it does happen. Mostly on the face of the block deck around the head bolt holes. It might be more the Conquest/Starquest/Starion engines due to boost or overtorqued bolts(?) Another place the blocks have been known to crack is the exhaust side of the block between the freeze plugs (this is on early Astron I 2.6 blocks) Generally the 2.6 block is a tough chunk of metal...

Thank you geezer. What goes into a full engine rebuild? What components get fixed/repaired?

geezer101
11-23-2021, 12:56 AM
Generally, the block gets hot tanked and goes through a check - cylinder bores, deck face and machined. Crank gets hot tanked as well, checked over and journals machined or linished depending on the condition (there are oil journals that pass through the crank and these can get plugged up with crud - if it dislodges after getting a once over it can wreck new bearings). Add new bottom end bearings for the main crank journals and the rods. Rods are retained. If it's just a freshen up you can get away with keeping the pistons, install new standard rings and a light hone of the bores. If the bores are no longer 'true' or have some scoring, factor in the block getting rebored and new pistons to match. If you've already got it apart then new timing chains and guides are on the list. Think about getting a replacement water pump too. Check clearances in the oil pump gears and inspect the housing for wear on the contact faces in the housings. Get a complete VRS kit with the rocker/valve cover and the half moon seal for the rear of the head. An engine rebuild is not a cheap endeavour, but as long as the machining is good and all the clearances are within tolerance you'll end up with an engine you won't have to mess with for 10 years.

*addendum - replace the rear seal. It'll suck to have the whole thing assembled and running sweet, only to have the rear seal fail and start drooling oil out of it...

BJH324JH
12-10-2021, 10:17 PM
Generally, the block gets hot tanked and goes through a check - cylinder bores, deck face and machined. Crank gets hot tanked as well, checked over and journals machined or linished depending on the condition (there are oil journals that pass through the crank and these can get plugged up with crud - if it dislodges after getting a once over it can wreck new bearings). Add new bottom end bearings for the main crank journals and the rods. Rods are retained. If it's just a freshen up you can get away with keeping the pistons, install new standard rings and a light hone of the bores. If the bores are no longer 'true' or have some scoring, factor in the block getting rebored and new pistons to match. If you've already got it apart then new timing chains and guides are on the list. Think about getting a replacement water pump too. Check clearances in the oil pump gears and inspect the housing for wear on the contact faces in the housings. Get a complete VRS kit with the rocker/valve cover and the half moon seal for the rear of the head. An engine rebuild is not a cheap endeavour, but as long as the machining is good and all the clearances are within tolerance you'll end up with an engine you won't have to mess with for 10 years.

*addendum - replace the rear seal. It'll suck to have the whole thing assembled and running sweet, only to have the rear seal fail and start drooling oil out of it...

Thank you geezer for the valuable information. The engine has been completely rebuilt. Is it unusual though that they used shellac on the headgasket? I've always have been told to install a headgasket dry. This shop also told me they would install American made pistons. I showed up one day uninvited and saw the box of pistons on the table.
Took a picture of the company and called them regarding where the pistons were made, they told me Taiwan. I then asked them to use a felpro head gasket, they didn't. He acted stupid and told me I never spoke with him about using a felpro head gasket. Which is a lie. He told me he was going to strip off all the rust away. Still rust on the pipe. He offered to paint over it! The engine was painted poorly. There is paint in places there shouldn't be, like the inside of the engine oil dipstick tube and the inside of where the water pump installs. He told me he would get rid of all the rust in the hot tank. I think he just painted over the rust. He also used shellac on the engine oil pan. It's probably going to be a bitch when I have to replace the oil pan gasket under the truck. I imagine the oil pan was just cleaned and they probably didn't even bother to remove the rust. Just painted over it. The bottom of the oil pan is also heavily scratched. I have a one year warranty, but, I'm afraid they won't honor it if anything goes wrong. I honestly don't feel comfortable this engine will last. There is just too many weird things that happened with the engine builders and the work they performed. What should I do?

dash
12-11-2021, 08:51 AM
Yeah... had my share of shitty machine shops/shady folk..... those lyin crooked bastards
Actually steered me toward purchasing 'good running' powerplants instead
dunno if you can scroll thru threads and find a contact for "Randy" or "Dad" we starquest folks call him.
older experienced knowlegable machine shop owner & starquest member enthusiast. Just the cool type we all like
Website had tons of 2.6 parts at great prices
greedy realtors basicly shut down his business..... under the guise of this covid bullshit
knock the wind out of him, I'd imagine.... but i think i recall him mentioning 'limited activity'
Too bad someone couldn't pick up where he left off. Good places AND people are gettin hella hard to find
Like the world has been in a downward spiral.... on a negative vibration. All 'good' fading away

https://www.starquestclub.com/forum/index.php?/forums/topic/9282-randy-dads-the-guy-for-engine-parts/#comments
https://www.starquestclub.com/forum/index.php?/forums/topic/137772-engine-rebuild-parts-aftermarket-and-oem-parts/

geezer101
12-11-2021, 01:35 PM
Oh FFS. It doesn't 'really' matter where parts are sourced from as long as the guys selling and installing it are legit. If they're billing you for gold and you get lead, they need to be called out. You can buy a decent turbo under $200 and it'll be made in China. Only reason why it's cheap is the sheer volume they can produce them at (yes there is garbage on the market) I am feeling your distrust with this shop and I can't blame you. Whole lotta BS vibes coming from them. Building an engine is a pain in the ass - sourcing parts, finding time to do it, trucks off the road, having the vaguest idea of WTF you are doing lol... these clowns will encourage you to DIY it. It's a horrible learning experience but you'll cut your teeth and save some money in the process.

I had a reputable shop do a bottom end and block for me. Did a good job too - hot tanked the block, decked and bored, straightened the crank. And then, the head... got it back, the main oil gallery was sealed and luckily I cracked it open before installing it. Full of BLASTING MEDIA. Poured out like sand from one of my work boots. This one oversight would've catastrophically destroyed the engine on first start. I've been using one shop since day one to do my head work, and this one time I went with the guys I'd chosen to freshen up an engine. Ask around, use google. You won't always get 100% satisfied customers or reviews as some people just can't be pleased and random things go wrong. But if you get a bunch of negative strikes you have a fair idea of what you're getting into with whoever is earning a bad rep.

BJH324JH
12-26-2021, 12:28 AM
I've installed the engine but what has me anxious is the distributor. Is there specific way to install a distributor or do I just stick it in the cylinder head, bolt it up and twist the distributor back and forth till it sounds good? Yup, I'm a newb at this.

geezer101
12-26-2021, 02:52 AM
There is a small dimple drilled into the shaft gear on the distributor that needs to be lined up with the alignment mark on the distributor body. This should get the rotor pointing before #1 post on the distributor cap. Make sure the crank is on TDC #1. Install the distributor with the cap off and the stud for the locking nut in the centre of the adjusting slot and push the distributor into the head. The rotor will move into position just before or onto the location of #1 post in the cap. Tighten the locking nut, install the cap and leads and start it up. If you've got it right it will fire straight up. Adjust the advance/retard on the ignition timing.

Now to have some fun. You will need a hand held tach/dwell meter. Remove the plugs and re-gap the electrodes to 0.85mm. Loosen off the distributor locking nut and start the engine. Hold the engine rpm @ 2000 and gently swing the distributor between advance/retard until you hit a sweet spot and the engine rpm's jump by themselves (might take 2 people to pull this off as holding rpm's fixed at one ratio can be tricky) Once you have found the sweet spot, back off the advance a tiny bit and tighten the distributor locking nut. Test drive and check for any signs of detonation/hesitation. If you've nailed it the engine will be nice and responsive, especially on gear changes.

Lanklo
12-27-2021, 09:55 PM
Call Clearwater cyl. Head in Fl. They are a rebuilder and fair prices. Replaced a couple and looked fresh and worked well. prices

BJH324JH
12-29-2021, 02:32 PM
There is a small dimple drilled into the shaft gear on the distributor that needs to be lined up with the alignment mark on the distributor body. This should get the rotor pointing before #1 post on the distributor cap. Make sure the crank is on TDC #1. Install the distributor with the cap off and the stud for the locking nut in the centre of the adjusting slot and push the distributor into the head. The rotor will move into position just before or onto the location of #1 post in the cap. Tighten the locking nut, install the cap and leads and start it up. If you've got it right it will fire straight up. Adjust the advance/retard on the ignition timing.

Now to have some fun. You will need a hand held tach/dwell meter. Remove the plugs and re-gap the electrodes to 0.85mm. Loosen off the distributor locking nut and start the engine. Hold the engine rpm @ 2000 and gently swing the distributor between advance/retard until you hit a sweet spot and the engine rpm's jump by themselves (might take 2 people to pull this off as holding rpm's fixed at one ratio can be tricky) Once you have found the sweet spot, back off the advance a tiny bit and tighten the distributor locking nut. Test drive and check for any signs of detonation/hesitation. If you've nailed it the engine will be nice and responsive, especially on gear changes.

Thanks, I'm going to try this and see how it goes.

BJH324JH
12-29-2021, 02:36 PM
Call Clearwater cyl. Head in Fl. They are a rebuilder and fair prices. Replaced a couple and looked fresh and worked well. prices

Ended up going with them.

BJH324JH
12-31-2021, 05:50 PM
For the timing, where are these alignment marks on the distributor? 27036

BJH324JH
12-31-2021, 07:08 PM
For the timing, where are these alignment marks on the distributor? 27036

I do see the drilled dimple. I just don't know what I align the drilled dimple to?

FMS88
01-01-2022, 02:58 PM
I do see the drilled dimple. I just don't know what I align the drilled dimple to?

From the FSM:

http://www.mightyram50.net/vbulletin/attachment.php?attachmentid=27037&stc=1

BJH324JH
01-02-2022, 11:32 AM
From the FSM:

http://www.mightyram50.net/vbulletin/attachment.php?attachmentid=27037&stc=1

Awwwww thanks, that clears up what geezer said. School was right, I am a visual learner.

Found this interesting piece of information as well:
https://www.yourmechanic.com/question/with-the-1-piston-up-were-should-the-rotor-button-be-pointing-by-windle

geezer101
01-02-2022, 02:04 PM
I wasn't 100% sure where the mark on the distributor body was located and I was too lazy to trawl through the PDF's to find it. Please tell me you got your engine firing right :pray: Now for the fun part - dialing in the tune and getting 'er to pull like a train :grin:

BJH324JH
01-02-2022, 10:44 PM
I wasn't 100% sure where the mark on the distributor body was located and I was too lazy to trawl through the PDF's to find it. Please tell me you got your engine firing right :pray: Now for the fun part - dialing in the tune and getting 'er to pull like a train :grin:

I got the engine up and running. Unfortunately, engine rebuilders screwd up on some things on the engine. The oil pan is leaking a crazy amount of oil in the rear of the engine pan. Right next to the transmission bell housing cover. Another thing, one of the engine freeze plugs literally popped right off into the street somewhere. Texted the engine shop for a new one, no responds. My engine almost over heated, I pulled over to the curb before it got too hot. Only went to the center on the temperature guage. All the coolant gushed out of the side next to the starter. Had to call triple AAA and get the truck towed 23 miles. It was cold and new years eve. Had to sleep in my truck in the freaking cold to wait for a tow truck. Thank God for the bench seat. The tow truck didn't arrive till the next day at 5 in the morning when I got woken up by a AAA technician calling my phone to let me know they found a tow truck driver. The crazy part about this whole experience is the tow truck driver lived across the street from where my truck was parked on the side of the road! Pretty cool driver, we chatted it up along the way back to my place. The guy has worked multiple jobs. Anyways, I bought the new freeze plug, needed my truck working again. Didn't have the time to argue with the engine shop. Getting the freeze plug was not fun! Let's put it this way, American public transportation is slow! Something 15min away takes an 1hour in the bus. Smeared permatex number 2 on the freeze plug and on the engine and hammered it in the engine. Went in smoothly. Although, I felt it could have been tighter. Hopefully it doesn't pop out again. Now the truck is back up and running but idles like crap. Doesn't stay on unless I gas it. I'm guessing this is a combination of the distributor and carburetor?

FMS88
01-03-2022, 10:54 AM
Which carburetor do you have? Mikuni or Weber? If a Weber make sure all the unused manifold vacuum ports are capped. If a Mikuni, check the hose routing, port connections and hose integrity. Also, check the eight-pin connector of the carburetor harness. A poor connection to the shut-off solenoid will prevent it from idling.

geezer101
01-03-2022, 01:29 PM
What an ordeal. Check for engine vacuum leaks, fuel delivery, carb settings like idle stop and A/F mixture then check the distributor install and timing.

xboxrox
01-03-2022, 03:15 PM
Which carburetor do you have? Mikuni or Weber? If a Weber make sure all the unused manifold vacuum ports are capped. If a Mikuni, check the hose routing, port connections and hose integrity. Also, check the eight-pin connector of the carburetor harness. A poor connection to the shut-off solenoid will prevent it from idling.

This 8 pin connector to the Mikuni carb became a big deal for me once; it caused the engine to idle like real crap ~ the fix ~ sprayed electronic cleaner & even used paint thinner in both male & female connector ends and used nylon brush rags Q-tips etc... to remove all the damn silicone I put in there to keep out the water & make good electrical contact ~ with the silicone grease removed the truck ran great again..!

BJH324JH
01-03-2022, 04:27 PM
Which carburetor do you have? Mikuni or Weber? If a Weber make sure all the unused manifold vacuum ports are capped. If a Mikuni, check the hose routing, port connections and hose integrity. Also, check the eight-pin connector of the carburetor harness. A poor connection to the shut-off solenoid will prevent it from idling.

I have a weber carburetor. 32/36 I believe.

geezer101
01-04-2022, 01:00 AM
I have a weber carburetor. 32/36 I believe.

Have to make sure you are using the right point on the Weber for the distributor vac advance or it'll be running advance all the time. If it was running before and it's set up the same, it's either picked up a vacuum leak and/or the ignition timing is off.

dash
01-04-2022, 07:40 AM
make sure u have 12v to carb solenoid, or they will idle like crap. Assuming cam & ignition timing are correct

geezer101
01-04-2022, 02:03 PM
make sure u have 12v to carb solenoid, or they will idle like crap. Assuming cam & ignition timing are correct

The Weber only runs an electric choke. There are variants that have a fuel circuit cut solenoid but they are only found on a few OEM fitted European cars.

SubGothius
01-04-2022, 05:51 PM
Have to make sure you are using the right point on the Weber for the distributor vac advance or it'll be running advance all the time. If it was running before and it's set up the same, it's either picked up a vacuum leak and/or the ignition timing is off.

Found out manifold vacuum is fine for ignition advance, even preferable, as long as you don't need to pass emissions testing. They only started using "ported" vacuum (taking vacuum from juuust above the closed throttle butterfly) to improve emissions at idle. Otherwise, manifold vacuum will apply full vac advance at idle, keeping the engine cooler and smoother-running at idle and improving fuel economy. Source:

http://chevellestuff.net/tech/articles/vacuum/port_or_manifold.htm

dash
01-05-2022, 10:12 PM
The Weber only runs an electric choke. There are variants that have a fuel circuit cut solenoid but they are only found on a few OEM fitted European cars
negative on that. My genuine redline conversion kit for toyota 3tc, definitely had the 'pencil-type' fuel solenoid 32/36
Connect just as oem toyota Aisin carb - one 12v+ for the solenoid, then the other thicker wire for the choke coil

geezer101
01-05-2022, 11:27 PM
negative on that. My genuine redline conversion kit for toyota 3tc, definitely had the 'pencil-type' fuel solenoid 32/36
Connect just as oem toyota Aisin carb - one 12v+ for the solenoid, then the other thicker wire for the choke coil

Odd. Was it an add on to the kit? I can find the idle cut solenoid as a separate part (it replaces the primary jet) but no kits with it as a complete unit.

*it appears that the fuel cut solenoid is only specifically suitable for Weber 32/36 DGEV with 'big' primary idle jets (didn't know there were different designed jets...) :shrug:

dash
01-06-2022, 09:12 AM
32/36 kit came like that. I've never actaully seen a oem-apllication 32/36. Seen a crapload of holley 5200s tho. Look like same carb
strange call to help a buddy sort out a weird 16V corolla, as he knew nobody who'd touch the new Aisin-copy carb, his son bought online
I happen to have gaskets spares, that fixed the prob. Car started half a crank, drove/idled perfect. Surprised how peppy it was!
I thought.... why are folks paying $400 to 'adapt' a 32/36, if this little $80 direct fit gem, performs the way it does ??
Performance prolly deterioates with age? dunno..

geezer101
01-06-2022, 10:25 PM
Yeah the Holley 5200 is basically a clone of a 32/36 DGAV. I've seen Webers on Ford Escort 1.6's and pushrod straight 6's from factory, and I pulled a 34DATA from a Lancia (which is an oddball carb in itself) Wonder how much difference there is in installing a 5200 on something like a 4G52/54 or G63B...

dash
01-08-2022, 05:16 PM
I 'adapted' a 5200 to a nissan 2.4L pickup, that had some weird oem 3-bolt carb pattern.
made a plate from 3/8 aluminium/ Carb nos ebay ~$80 iirc. Got the job done
Owner said even if a weber 32/36 kit was avaiable, no way was it worth $400 to him

pennyman1
01-15-2022, 07:59 PM
the Holley - Weber 5200 carb is an emissions carb with all kinds of wacky bits that can clog and go out of adjustment. Because of the complexity, many of the rebuilt 5200s are poorly rebuilt, and will run poorly. They will bolt to the same adaptors as the weber, but I have the same Weber on Geronimo since 1983, so is 300-400 too much for a good running carb?

dash
01-17-2022, 10:01 AM
same $400 question came to mind, after the recent rolla experience. Why ?
Car ran crappy. Needed a carb. $80 later (Aisin oem copy, Alibaba I think he said) = solid running/performing vehicle
I'd welcome any carb mitsu pickup that equalled that rolla. Will it last ? dunno. Mitsu version available ? Never looked.

early 5200 are not "emission carbs". Naked as any bare bones weber. Early 70s pinto 2000cc & chevy vega 2300, for eg.
Oem car warranty, so you know 5200 functioning & longevity had to be top notch. Now those later chrysler 5200s - whoa! Run
Point was.....
If you have the time, skill, knowledge... avenues open up. In essence, the sub $100 nissan/5200 carb job. $400... 'optional'
Idea only came to mind, remembering vega carb looked same as my rwd rolla 3TC $170 weber kit.. (then onto $450 mikuni sidedrafts)
Grew older/wiser. Turbo swaps made toooo much more sense. Overall cheaper, actually if diy. Performance difference.... a joke.

BJH324JH
01-19-2022, 12:35 AM
Figured out why the engine wasn't idling properly. :) It was a loose brass screw, tightened her up and now it idles. I guess vibration loosened it up possibly? Although, now it idles very high. A friend suggested doing a compression test. He said that can give me an idea of the work the engine builders performed. What kinda of results should I be getting on the compression test for my g54b engine?

SubGothius
01-19-2022, 03:44 PM
A friend suggested doing a compression test. He said that can give me an idea of the work the engine builders performed. What kinda of results should I be getting on the compression test for my g54b engine?

Main thing is to look for roughly even figures across the board; a little variation is okay, as long as you don't have any cylinder(s) wildly off vs. the others.

That said, bad compression would tend to manifest as rough/uneven running like a misfire, not just a high idle.

geezer101
01-20-2022, 06:41 AM
+1 on that. Drop in compression will cause low/rough idle, hard starts, loss in power. High idle can be a vacuum leak, over advanced ignition timing or incorrectly adjusted carb. Go back and reset the idle screws to bring the idle down and you should be in the ball park.

dash
01-21-2022, 05:15 AM
elrctric choke coil should be getting 12V(& warm).... otherwise may take a long time to idle 'normal'