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questions replacement 2.5

1K views 11 replies 5 participants last post by  bherron1 
#1 ·
I'm looking at a replacement engine for my 2.5. I found one with all accessories except alternator. Cost is $400 I'm in Cleveland Ohio it seems to be a good price. Engine has 175k is that too many miles? If I do a compression check what kind of #'s should I be looking for?
Any advice from anyone? Never replied and engine and probably going to do the clutch while it's out. I believe I have an internal master cyl. ('93).

Thanks!
 
#2 ·
For an engine with that many miles I would see what it looks like in terms of seals and whatnot. But as far as compression is concerned, for an engine with that many miles, I would be concerned if it was anything lower than 95psi. Anything lower than 95 and you would probably be looking at a rebuild soon.
 
#3 ·
That's why I am replacing now. I currently have like 115,120, 100, & 60 in my current motor. When I did a wet test the 60psi cyl jumped to 120 ish. I don't want to rebuild no do I know how.

Is a visual inspection on the seals enough? The "whatnot" is what I'm looking for. But I guess if I need a part I can take it off my current motor.

Even though if I can unbolt it and put a new gasket on before I install it I probably do it.. Now that I think about it I'll definitely do the valve cover and the oil pan before I put the replacement in. Is the head gasket the same? Or should you have to have it machined if you pull it?

Maybe it's worth it to have mine bored and try to do it myself? I am just really nervous to install something stupid (like a ring) backwards, and I really don't wanna do this twice. Once I get into water jackets and valve lash or plastic shimming and stuff like that I'm lost. (well never done it before) I have rebuilt a power window motor, alternator, done starters, brakes, done plenty of struts/shocks, fuel pumps ball joints and put the lift on my Jeep, I do all the maintenance but nothing like this on that mechanical level.
 
#4 ·
Check out a rebuilt short block, and if you have to, reuse your head with out a rework at this time. I know this is not the best way to do things, but it will buy you some time to save the money to have the head reworked at a later date and just be out the extra cost of another head gasket when you do get the head work done. As for as shimming the valves, that is not done on your engine as for as I know, it's a straight forward job, follow the book and all will be great. If you can do all the other work you say, then you can do this easy.
 
#7 ·
I did a rebuild in my driveway by my self. Really its not that hard.. I pulled the head and sent it to a machine shop to be tested. (It was bad) I dropped the pan pulled the pistons, rods and lifters. I honed the cylinders with a battery operated drill and hone from auto zone. Then installed new rings put the pistons back in with new bearings. I installed new lifters and rods because they were cheap and I was already there. then bolted on the New head. Are you getting any blow by? is there oil coming from the hose attached to the valve cover going to the air filter? As for cost the new head was 500$ and the rebuild kit was about 3-400 Cant quite remember.
 
#8 ·
It's closest to the radiator cylinder @ 60psi is the culprit I believe.

Yes I'm getting blow by the valve cover puffs like a train. I am 100% sure the ccv is operating correctly.. If I don't keep a breather in place of the oil cap it leaks excessively.

I could be over thinking it just don't want to get in over my head doing a rebuild.
How to you know how much to hone? Do they all have to be the same diameter?
 
#9 ·
FROM JEEP SERVICE MANUAL---​
HONING CYLINDER BORES​
Before honing, stuff plenty of clean shop towels under​
the bores and over the crankshaft to keep abrasive​
materials from entering the crankshaft area.​
(1) Used carefully, the Cylinder Bore Sizing Hone​
C-823 equipped with 220 grit stones, is the best tool​
for this job. In addition to deglazing, it will reduce​
taper and out-of-round as well as removing light​
scuffing, scoring or scratches. Usually a few strokes​
will clean up a bore and maintain the required limits.​
CAUTION: DO NOT use rigid type hones to remove​
cylinder wall glaze.​
(2) Deglazing of the cylinder walls may be done if​
the cylinder bore is straight and round. Use a cylinder​
surfacing hone, Honing Tool C-3501, equipped​
with 280 grit stones (C-3501-3810). 20-60 strokes, depending​
on the bore condition, will be sufficient to​
provide a satisfactory surface. Using honing oil​
C-3501-3880 or a light honing oil available from major​
oil distributors.
CAUTION: DO NOT use engine or transmission oil,​
mineral spirits or kerosene.​
(3) Honing should be done by moving the hone up​
and down fast enough to get a crosshatch pattern.​
The hone marks should INTERSECT at 50° to 60°​
for proper seating of rings (Fig. 1).​
(4) A controlled hone motor speed between 200 and​
300 RPM is necessary to obtain the proper crosshatch​
angle. The number of up and down strokes per​
minute can be regulated to get the desired 50° to 60°​
angle. Faster up and down strokes increase the crosshatch​
angle.​
(5) After honing, it is necessary that the block be​
cleaned to remove all traces of abrasive. Use a brush​
to wash parts with a solution of hot water and detergent.​
Dry parts thoroughly. Use a clean, white, lintfree​
cloth to check that the bore is clean. Oil the​
bores after cleaning to prevent rusting.
 
#10 ·
All that blow by is a dead give away of worn rings.
When I removed my pistons there was no score marks on the cylinder walls. Thus I gently honed the cross hatch as stated above.
IF Yours has bad scoring to the cylinder wall then you would need to send it to a machine shop to be bored / honed.
Yes your cylinders should be the same diameter (Unless badly damaged)
If you do this get a factory service manual. It will have all the information you need.
I used a Chilton manual but the one from the factory is better.
 
#12 ·
I did the complete rebuild after sending block crank and head to machine shop. FSM is a must but if you can read and understand what you read its a go. My engines runs like a brand new 1995
 
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