Rebuilt motor "ticking" from what sounds like front cover and water temp question.

[Leadfoot]

First, I found my mystery wire is for temp sender. There is a 1/8th sender unit with single spade on the thermostat housing itself (pegs needle) and one just below it and closer to the carb on the intake manifold. Which one is it supposed to go to and are there usually two?

Now the biggee. Rebuilt the engine: honed cylinders, new bearings, reused oil pump and cam timing chain (less than 5K on them both), installed balance shaft eliminator, new rings, new rebuilt head as the original cracked and was reason for rebuild). Adjusted the jet valves cold.

Engine fired fine but now it ticks. It sounds as if it's coming from the front cover? I'm going to pull the valve cover with the truck "nose end down" and run it for a short time to see if I can pinpoint the noise. I understand a lifter tick, or a jet valve out of adjustment tick, but would could tick under the front cover?

[pennyman1]

Which motor are you working on, and to eliminate the jet valves as the ticking noise, back the adjusters off until they don't contact the valves at all or remove the screws. Check the chain guides for good padding and that they did not come loose, and check the timing chain tension to ensure it does not have too much slop in the chain.

[Leadfoot]

Well the ticking was from the front cover. It appears the oil pump gear bolt backed off and pushed it's way through the front cover. Which would explain why the engine purred at first (10-12 minutes), then I heard a pop, and then the ticking started. I am having trouble posting pics, but I can email them to someone if they can post.

No damage other than I had to pull the cover, clean the first few bolt threads and first few threads on pump shaft, weld the cover and reassemble using loc-tite this time.

The only issue I'm having now is the water temp sensor. In the actual thermostat housing cover (where the upper hose attaches) there is a single prong sensor (plug it in there and as soon as you hit the key it's pegged), and just below it in the manifold there is a single prong sensor (doesn't peg needle but not sure it works). BOTH are 1/8" NPT, but when I went to get a new single prong sensor, all they have are the larger M16 threads....? Also there is only one unused wire with single female spade connector, so was one sensor "added" by a previous owner or am I missing something (maybe there was an issue)? Also my truck has no A/C, would one sensor have been for that?

Anyone know the Ohm value so I could cross reference (89 2.6L)?

Other than that, I'm putting back together (which fresh oil and filter AGAIN) and going to give it another shot. :-)

[Leadfoot]

I look up in the autozone (I know, I know) website and they show part number TU68 as fitting my truck but it's an M16 thread. The large two prong unit is most likely an M16 but the two smaller ones that are single wire look to be closer to an american 1/8 such as the TU89 they have listed (although it says it won't fit my vehicle). Anyone have a part number for a small diameter (much smaller than an M16 thread) single wire temp sender unit for this engine?

[camoit]

Look in the sight news and support for the "how to" on putting up pictures. We have lots of info in there on this topic.

[Leadfoot]

225422552256

Truck is running, no noises from motor, slight vacuum leak (haven't narrowed it to carb or intake but when spraying carb clean between the two the idle picks up, right front caliper is froze (need to address that), and rebuild idler arm pivot.

Still love this truck though and the motor looks good all painted (will take some more pics installed).

[camoit]

I see you got the picture thing figured out. Now you can show us more.... We like pictures...

[camoit]

Any updates on this??

[Leadfoot]

All set. There were two water temp sensors. I ended up using the one in the intake manifold. Was able to bring it in to NAPA and they found one (will have to check p/n). I only had it on the road a few days when I noticed the rear frame was shot. Took months to get it back going, then (see other thread), the rear brakes went out (only driven it a few hundred miles). Now I'm in search of fuel tank and sending unit.

Here is a highlighted picture of cracked cover and backed out bolt. Luckily an easy fix. Just haven't gotten to drive it much since :-(

3098

[Leadfoot]

Some more pics

3099

3100