Jet Valve trouble?

[Doc Rochester]

Hey gang-

I am a recent returnee to the Ram 50 fold. In the past, I have owned a couple of TurboDiesels and have also owned an '87 2wd long bed with a 2.6. The 2.6 was the most trouble free vehicle I have ever owned- it went 223k with only tires and brakes as maintenance before I had to put chain guides in it. But, I sold it, having 3 kids and needing more seats for tethering them in.

So, after a 12-year hiatus, I have recently acquired an '88 Ram 50 4x4 Extended Cab with a fairly fresh 2.6 short block (w/ 22K miles). I've only owned it a couple of days, and so haven't done any close examination aside from the very superficial. The engine runs very rough at idle and seems to have a consistent low-level backfiring through the carburetor. At least that's what it sounds like through the air cleaner.

As I implied earlier, I don't really have any hands-on experience with the 2.6 engine, aside from a lot of scuttlebutt from my various Mitsu pals. At a minimum, the initial consensus is that I would be wise to do an ignition tune-up (including wires).

But, I've had a little bit of experience with other engines with the same general symptoms. In those cases it was either a bad cam lobe on an exhaust valve, or otherwise a bad intake valve.

So, as I said, not having any experience with these engines otherwise, I would be curious about the following:

1) Do these engines have a problem with burning or sticking jet valves?

2) I it possible to eliminate the actuation of the jet valves by deleting the rocker arms for them?

3) Is the backfiring symptom simply a minor issue of a malfunction of the air bleed valve in the carburetor?

4) Do the 2.6 engines have any notable history of burning valves?



Your thoughts?



FWIW, this vehicle is in quite good shape for a vehicle in Western New York State. It is definitely a keeper. My long term plans are to prepare a 2.4 engine with a 16-valve head and also go with turbocharging and stand-alone engine management. (I have a lot of experience doing so with VW and Audi 4 and 5 cylinder engines.) But, I would like to use the truck while I prepare a new engine.

[Spicoli]

I wouldnt sya burning the jet valves out, more that they have a habit of getting hot and cracking out the head.

Yes, get em here http://www.enginemachineservice.com/

Dont know

Theres been a few Ive heard of burning em out but I wouldnt say its terribly common.

[pennyman1]

to eliminate the jet valves quickly, just back out the adjuster screws on them - they are the ones on the side of the intake rockers. They should all come up to the same height - if not, gently pull them up till they all match. Also pull the EGR valve on the side of the intake under the carb, that can cause your rough idle if its stuck open all the time. Make sure all the vacuum lines in the metal box on the drivers inner fender are good - they rot off or get chewed off and then send screwy signals to the computer controlled carb.