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86 ranger 4x4 no compression #2 cylinder


4x4ranger86

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ok well i just bought an 86 ranger for $550.00. it runs but not very well. I did a compression check (engine wasnt warmed up)

#1 150 psi
#2 0 psi
#3 130 psi
#4 130 psi
#5 130 psi
#6 125 psi

i added some oil to number 2 and retested multiple times. no change. also my battery was starting to die towards the end especially during the last cylinder check, so im guessing the last four cylinders are slightly higher than 125 - 130 but even if they are not its still pretty good pressure.

this engine also has the after market cylinder heads so im pretty sure its not the cylinder head itself. (the whole top end looks like it has been redone recently)

since i added oil and there was no change in the pressure i am ruling out piston rings as the sole cause. (possibly bad rings with a combination of other problems though)

the piston is moving up and down and there isnt a loud noise that would indicate a busted rod.

so that leaves the head gasket, valves, lifters, cylinder cracked, or a hole in the piston right? anything else it might be?

im really hoping that it is a valve that is stuck open. i rotated the engine by hand and the lifters are all fairly loose as in you can spin them with your fingers if you try hard enough. the #2 intake lifter is the only one that wont move at all.

anyways i am basically looking for information/suggestions on how to adjust the rocker arms, lifters, and valves. i have been reading these forums for the past few days and although it has been discussed a few times i really dont understand exacly how to go about doing it. alot of people say that the hydraulic lifters on the 2.9l never need to be adjusted and only the 2.8l needs regular adjusting. is that true?

i dont want to pull the heads until i rule out the misadjusted valves. thanks in advance. sorry for such a lengthy post.
 


Big Jim M

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It's really hard to get ZERO pressure... unless the intake valve is NOT opening or the exhaust valve isn't closeing.. Or the piston is ruint.
My very first guess would be the cam lobes are ruint and not supplying lift to the intake valve.
Charge the battery and then hit the starter while watching the lifters on that cylinder.
If they are opening as designed then you need to take that head off and see if the piston as a hole in it or what is going on in there.
Big JIm
 

n_grimm

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Adding to the good advice Jim gave, if you have a blown piston it should be puffing thru the valve cover when you remove the pcv valve. Also I would loosen the tight valve until you get a little clearance just to be sure it is closing.
 
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4x4ranger86

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found the problem

well i pulled the heads today and found out #2 piston was shot. it must of overheated and melted inward or something as there was a big gap between the clinder wall and the piston. i guess i will be redoing the bottom end in the near future.

i really dont want to get too crazy with a rebuild, but do you think i can get away with just new pistons and bearings, and get the cylinders honed? i already have resurfaced 89 heads from another truck and the valves were redone as well. got new headbolts and gaskets and brand new exhaust manifolds as the other ones were cracked. i know it really comes down to what i find during the tear down, but do you guys reccomend anything else?

i also have the other bottom end from my 89 ranger that i was originally going to rebuild until i found this 86. the 89 is 2wd and single cab and way more beat up, so id much rather put the time and money into the 86. the bottom end from the 89 is basically the same problem, but nowhere near as bad. #6 piston has a small gap/notch between the cylinder wall. it still had decent compression, but i didnt want to put it back together like that. i only pulled the heads on the 89 as i suspected they might be cracked. they were just warped and the main culprit on that one was the cracked exhaust manifold.

anyways i was also thinking of just doing this cheap and using a good piston from the 89 and putting it into the #2 cylinder in the 86. do you think i could get away with that? it would save me alot of time and money right? but i also realize that if i have the engine pulled and have gone to that much trouble i might as well redo them all and have something that i know will last. just trying to decide which way to go.

any ideas/suggestions would be greatly appreciated. thanks in advance.
 

Big Jim M

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From your description I'd guess you had an intake leak that was leaking AIR and the #2 had a blow torch in it.. Your engine is a prime example of a vacuum leak.
Also from your compression check, if it was done correctly, I'd be for checking both blocks and using the best one.. I'd be honing and reringing and all that stuff to the best one. However it ain't my money. If you are really short then scavange a rod and piston from the other engine and put her back together with only one set of new rings.
When you pull that piston you will have a good look at the bearing... You might even get away with only one rod bearing.
By the way... most of the world would do it the cheap way, and their engines run forever too..
Big JIm
 

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