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So this is not really a repair question, but more of a your thoughts.
This is my stepsons truck and it has a number of issues including a leaking valve seal on number 4, exhaust manifold leak on 4 and 6 and a couple of other minor issues like a fuel injector plug that is broken and can come loose.
So relatively minor issues though he threw a bunch of parts at the truck trying to fix a intermittent start/idle issue especially when cold, which ended up being the number 4 spark plug was very badly fouled, due to the leaky exhaust valve seal I mentioned, and a new spark plug fixed that at least temporarily.
So before I started putting more parts and money (truck in general good shape but most bushings and suspension are in need of replacing). I did a compression test on the motor. I listed the results both dry and wet at bottom. I did the test twice on different days just to verify and results were within a couple of psi of each other. Truck tends to run good in my opinion it's low on power but its really used more as a daily driver not for real work.
So the question is the numbers aren't great but truck tends to run decent. What do you guys think? Go ahead and fix the leaking valve stem and exhaust manifold gasket and just keep running it? Or just save the money and plan on a rebuild/replacement? While OBS trucks are coming up this is not a super clean truck with low miles I think the truck isn't worth a rebuild and he should just send it down the road and move on with a new vehicle.
with those numbers you could go either way, but just having the heads redone would be less expensive for now and last a long time. the other thought is have you tried readjusting the rockers that may help bring numbers up on a few cylinders.
overall looks fairly good though per spec 3 cylinders are questionable but valve adjustment may help those.
I would really want to do a cylinder leak down test even just putting low pressure air into a cylinder into each cylinder on the compression stroke an listening to crankcase breather and inlet to exhausr to listen for leaking air,
" We're trying to plug a hole in the universe, what are you doing ?. "
(Walter Bishop Fringe TV show)
So I am borrowing a compression leak down tester from a friend I'll get back to you once I have the results. From just adding some pressure to cylinders while doing the pressure test the only pressure I was hearing was blow by from piston rings. I personally believe with 250,000 on the clock that rings are starting to go out.
Thanks to all of you for your input. I'll get back to you once I get the leak down results back.
