Discovered Bore

I had one rod journal on my crank that was worn pretty badly. It caused one cylinder to foul badly. When I disassembled it looked almost identical to yours. I don't know what your accompanying symptoms are. My machinist had to send the crank out , but as I understand it, the process is basically spatter welding, and regrinding to spec, so I paid about 120 bucks to have the crank built up and evened out. We chose 40 over instead of 60 over (viable with 258) on the cylinders, rebuilt and no problem. If the cylinders check out okay, I'd re-ring over sized, check all bearings/surfaces first. I wanted to do a rebuild, but you may WANT a new motor instead. If I could do that part again, I'd have spent the initial money on a running motor and rebuilt more as a rec project. I have not followed this too closely, so I am not aware of all of your observations, I would think that if the crank end of the rod were causing the problem, you would hear some sort of slapping noise, but I do not know what you may observe if it were at the other end.

Don't sweat the 40 over part, I get smoking deals on motor parts, and still ended up spending 750 on a total motor rebuild. plus 200 on elective kinds of crap, That may have been why people advise you to replace. Whole motors, "running when pulled" type of things, can be had much cheaper.

| > I saw a 'generic' rebuilt engine quote. | >

| > They only fix what is messed up on those kind of quotes.... | >

| > Still looks like a gas washed cylinder to me though... | >

| > Mike | > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 | > 88 Cherokee 235 BFG AT's | >

| > William Oliveri wrote: | > >

| > > Looks like my pistons are .40 over. There's a 40 on top of the pistons. | |

Reply to
Fennidh
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Reply to
Steve G

Thank you for your time on this response Steve, Fennidh, all.

A couple of things. I did not change the injectors around so there was no results to indicate whether it was the injector or not. Also, The cold leak down test on #2 was significantly higher than the following warm engine test. Also, you are correct in that I could not detect any fuel smell in the oil (I checked again when my nose was better).

Regarding the Rod theory, I had been hearing some noise on a cold engine which did dissipate as it warmed up. Larie at JeepsRUs also mentioned hearing a noise in the engine when I was there for DRB diagnostics so this is a possibility.

Can someone describe what to look for at the Rod/Bearing/Crank level if this is the problem? Will the bearings be loose when I move it back and forth?

Thanks,

Bill

Reply to
William Oliveri

Reply to
L.W.(ßill)

Reply to
L.W.(ßill)

I deleted the pics, sorry, the journal in question on mine was visibly damaged at the point where the polished journal met with the rough cast lobe, and subsequently undersized. If this is a problem, and it caused the rings to break or fail in some way, fixing the rings alone is temporary, I'd at least remover the rod cap, and check that journal. Any problem there will be visible. Somewhere someone, perhaps many, suggested the rings, sounded pretty well backed up too. I'd pull that piston and re-ring that one, and once you see how easy that is, you'll probably do them all. Make sure that it was not caused by something else.

FWIW, the cyl walls on mine were absolutely beautiful when I took it down, I had a terrible slap by the time I did the real repair, and was anticipating wall damage. I was pretty shocked. Renewed my faith in that particular motor. I don't think any one thing is going to lead you to the source of your situation. But, checking out that piston/rings seems like it might give you a handle.

| > > If the purge valve is blown, it effectively shuts down the PCV system so | > > oil blows into the air filter. | > >

| > > The only test I know is to pinch off the line from the canister to the | > > PCV system at idle to see if the idle changes. If the idle changes, the | > > canister purge is dead. | > >

| > > A dead canister will also cause an unstable idle speed. It will vary up | > > and down and surge slightly. | > >

| > > No, a dead canister will not just get one cylinder 'wet'. I also don't | > > believe a dead canister or blow by of any type can pool oil in the | > > bottom of the intake manifold or in the individual fingers leading to | > > the cylinders. | > >

| > > When my air filter filled with oil, it dripped out on the ground. The | > > lip of the intake prevents oil from dripping down the throat of the carb | > > or TB unless the oil in the air filter is deeper than

1/4" or so and you | > > have the air filter that sits on top of the carb or TB. | > >

| > > I still think gas and bad injectors man..... | > >

| > > How was the gas mileage on that engine? | > >

| > > If it was mine, I think I would put the carb back on and see what | > > happens before spending a dime on it. | > >

| > > Mike | > >

| > > William Oliveri wrote: | > > >

| > > > Mike, | > > > Is there any way to test a charcoal can detatched from the jeep? | > > >

| > > > Would a bad charcoal Can cause the effect like we see in #2 cylinder? | > > >

| > > > When I checked the other items (air filter tube/housing, pcv tube, | > throttle | > > > body) I also looked at the air filter. It was dirty at the bottom but | > > > nothing that bad. Remember, this air filter is sprayed with oil so | the | > oil | > > > I sprayed it with accumulated at the bottom. Like an ounce or so. | You | > > > couldn't even get your hands wet with it. Not to the degree you | > discribe. | > > >

| > > > Bill | > > >

| > > > > You need someone that knows engines and isn't just out to take you | > > > > money. | > > > >

| > > > > Something really strange is going on..... | > > > >

| > > > > What you are now describing is blow by, big blow by. | > > > >

| > > > > You cannot have this with 150 psi compression unless the PCV valve | is | > > > > just plain broken or shut off from a bad charcoal canister. | > > > >

| > > > > What did your air filter look like? It 'must' have been just full | of | > > > > oil to have the intake with oil pools in it. | > > > >

| > > > > If it wasn't full of oil, then you do not have 'blow by'. | > > > >

| > > > > You also 'must' have had one big blue cloud following you with the | > > > > amount of oil you describe in the intake, no two ways about it. | > (unless | > > > > it is gas wash) | > > > >

| > > > > You are aware that a dead charcoal canister will produce enough blow | b | > y | > > > > to really imitate a blown engine right? It will soak an air filter | in | > a | > > > > week. | > > > >

| > > > > I am really almost thinking that someone sold you a dead FI system. | I | > > > > think it was broken and giving them the same fits and strange | symptoms | > > > > you are getting so they unloaded it on you. | > > > >

| > > > > Gas wash is very strange if you haven't seen it before. It takes | very | > > > > little gas to wash down the dirt and oil and make a messy slurry | that | > > > > almost looks like oil. This can pool in an intake manifold or into | a | > > > > piston. | > > > >

| > > > > You are describing injectors leaking down and pooling in the intake | or | > > > > 'gas wash'. | > > > >

| > > > > Good luck Bill! | > > > >

| > > > > I am out of ideas. | > > > >

| > > > > Mike | > > > >

| > > > > William Oliveri wrote: | > > > > >

| > > > > > I took the intake manifold to a perfomance shop today to have the | > > > injector | > > > > > in question tested and the mechanic told me it's highly unlikely | to | > be | > > > > > cylinder wash. He looked at the intake manifold and saw oil in | each | > > > > > manifold "finger" (which I didn't see before) and when he opened | the | > > > > > throttle there was a pool of oil in the there. When I looked in | the | > > > same | > > > > > place when the intake was on the engine I didn't see a drop. I | felt | > and | > > > ran | > > > > > a q-tip inside the pcv valve hose and didn't come back with any | oil | > > > stains. | > > > > > I put my hand inside the filter hose which connects to the | throttle | > body | > > > and | > > > > > I didn't feel any oil there either. Of course, this was closer to | > when | > > > I | > > > > > started this process and not in the later days. Could be it got | > worse | > > > in | > > > > > the end or was pooled in the intake and didn't show up in the | > throttle | > > > body. | > > > > > He told me Blow By was going on and I needed a new engine. | > > > > >

| > > > > > Is there anything else that could be going on as I'm getting ansy | > about | > > > > > pulling this piston. Could there be some effect which is | affecting | > only | > > > #2? | > > > > > Should I have him test #2 injector anyway and see what he finds? | > > > > >

| > > > > > Thanks, | > > > > >

| > > > > > Bill | > > > > >

| > > > > > > I saw a 'generic' rebuilt engine quote. | > > > > > >

| > > > > > > They only fix what is messed up on those kind of quotes.... | > > > > > >

| > > > > > > Still looks like a gas washed cylinder to me though... | > > > > > >

| > > > > > > Mike | > > > > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 | > > > > > > 88 Cherokee 235 BFG AT's | > > > > > >

| > > > > > > William Oliveri wrote: | > > > > > > >

| > > > > > > > Looks like my pistons are .40 over. There's a 40 on top of | the | > > > pistons. | >

| >

| |

Reply to
Fennidh

Sorry, as for loose, mine were varying in "looseness" at tear down. During build, I checked them to compare and they were much more secure. Make sure the rod does not "come away" from the journal in any manner, at all. try pushing one bolt toward the other so to speak, there should not be any play that way. I am not great at this stuff, but if there is no damage to the journals, remember that those bearings come in oversized thickness',

Good luck.

| > > If the purge valve is blown, it effectively shuts down the PCV system so | > > oil blows into the air filter. | > >

| > > The only test I know is to pinch off the line from the canister to the | > > PCV system at idle to see if the idle changes. If the idle changes, the | > > canister purge is dead. | > >

| > > A dead canister will also cause an unstable idle speed. It will vary up | > > and down and surge slightly. | > >

| > > No, a dead canister will not just get one cylinder 'wet'. I also don't | > > believe a dead canister or blow by of any type can pool oil in the | > > bottom of the intake manifold or in the individual fingers leading to | > > the cylinders. | > >

| > > When my air filter filled with oil, it dripped out on the ground. The | > > lip of the intake prevents oil from dripping down the throat of the carb | > > or TB unless the oil in the air filter is deeper than

1/4" or so and you | > > have the air filter that sits on top of the carb or TB. | > >

| > > I still think gas and bad injectors man..... | > >

| > > How was the gas mileage on that engine? | > >

| > > If it was mine, I think I would put the carb back on and see what | > > happens before spending a dime on it. | > >

| > > Mike | > >

| > > William Oliveri wrote: | > > >

| > > > Mike, | > > > Is there any way to test a charcoal can detatched from the jeep? | > > >

| > > > Would a bad charcoal Can cause the effect like we see in #2 cylinder? | > > >

| > > > When I checked the other items (air filter tube/housing, pcv tube, | > throttle | > > > body) I also looked at the air filter. It was dirty at the bottom but | > > > nothing that bad. Remember, this air filter is sprayed with oil so | the | > oil | > > > I sprayed it with accumulated at the bottom. Like an ounce or so. | You | > > > couldn't even get your hands wet with it. Not to the degree you | > discribe. | > > >

| > > > Bill | > > >

| > > > > You need someone that knows engines and isn't just out to take you | > > > > money. | > > > >

| > > > > Something really strange is going on..... | > > > >

| > > > > What you are now describing is blow by, big blow by. | > > > >

| > > > > You cannot have this with 150 psi compression unless the PCV valve | is | > > > > just plain broken or shut off from a bad charcoal canister. | > > > >

| > > > > What did your air filter look like? It 'must' have been just full | of | > > > > oil to have the intake with oil pools in it. | > > > >

| > > > > If it wasn't full of oil, then you do not have 'blow by'. | > > > >

| > > > > You also 'must' have had one big blue cloud following you with the | > > > > amount of oil you describe in the intake, no two ways about it. | > (unless | > > > > it is gas wash) | > > > >

| > > > > You are aware that a dead charcoal canister will produce enough blow | b | > y | > > > > to really imitate a blown engine right? It will soak an air filter | in | > a | > > > > week. | > > > >

| > > > > I am really almost thinking that someone sold you a dead FI system. | I | > > > > think it was broken and giving them the same fits and strange | symptoms | > > > > you are getting so they unloaded it on you. | > > > >

| > > > > Gas wash is very strange if you haven't seen it before. It takes | very | > > > > little gas to wash down the dirt and oil and make a messy slurry | that | > > > > almost looks like oil. This can pool in an intake manifold or into | a | > > > > piston. | > > > >

| > > > > You are describing injectors leaking down and pooling in the intake | or | > > > > 'gas wash'. | > > > >

| > > > > Good luck Bill! | > > > >

| > > > > I am out of ideas. | > > > >

| > > > > Mike | > > > >

| > > > > William Oliveri wrote: | > > > > >

| > > > > > I took the intake manifold to a perfomance shop today to have the | > > > injector | > > > > > in question tested and the mechanic told me it's highly unlikely | to | > be | > > > > > cylinder wash. He looked at the intake manifold and saw oil in | each | > > > > > manifold "finger" (which I didn't see before) and when he opened | the | > > > > > throttle there was a pool of oil in the there. When I looked in | the | > > > same | > > > > > place when the intake was on the engine I didn't see a drop. I | felt | > and | > > > ran | > > > > > a q-tip inside the pcv valve hose and didn't come back with any | oil | > > > stains. | > > > > > I put my hand inside the filter hose which connects to the | throttle | > body | > > > and | > > > > > I didn't feel any oil there either. Of course, this was closer to | > when | > > > I | > > > > > started this process and not in the later days. Could be it got | > worse | > > > in | > > > > > the end or was pooled in the intake and didn't show up in the | > throttle | > > > body. | > > > > > He told me Blow By was going on and I needed a new engine. | > > > > >

| > > > > > Is there anything else that could be going on as I'm getting ansy | > about | > > > > > pulling this piston. Could there be some effect which is | affecting | > only | > > > #2? | > > > > > Should I have him test #2 injector anyway and see what he finds? | > > > > >

| > > > > > Thanks, | > > > > >

| > > > > > Bill | > > > > >

| > > > > > > I saw a 'generic' rebuilt engine quote. | > > > > > >

| > > > > > > They only fix what is messed up on those kind of quotes.... | > > > > > >

| > > > > > > Still looks like a gas washed cylinder to me though... | > > > > > >

| > > > > > > Mike | > > > > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 | > > > > > > 88 Cherokee 235 BFG AT's | > > > > > >

| > > > > > > William Oliveri wrote: | > > > > > > >

| > > > > > > > Looks like my pistons are .40 over. There's a 40 on top of | the | > > > pistons. | >

| >

| |

Reply to
Fennidh

What a great idea!!!!

http://picti> >

Reply to
William Oliveri

One of his first complaints was no spark on that cylinder. I said gas issues.

He has not changed injectors.

Mike

Steve G wrote:

Reply to
Mike Romain

I have just put a mattress down and flipped a vehicle over like that for work... It was an Austin Mini that needed off road skid plates though not a Jeep.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

William Oliveri wrote:

http://picti> > >

Reply to
Mike Romain

There is lots of good advice here for you Bill. I don't know which way you are leaning on this right now, but let me suggest this to you: get a rebuilt engine from a reliable source, and put it in yourself. If you can pull a cylinder head, you can replace the engine. An engine hoist doesn't cost much to rent for a day, or weekend, and you can pocket all that extra cash instead of paying a mechanic to install it. It seems intimidating at first, but once you tear into it, it actually isn't as much work as you might think.

The plus side, beyond the obvious cash advantage, is the tremendous knowlege you will gain by having done it yourself, and the job satisfaction when you turn the key and know that YOU made it fire. There may not be any more gratifying sound than that of a newly-fired engine which you installed yourself.

Jerry

Reply to
Jerry Newton

The part that fails is the purge valve diaphragm. It's operated by ported vacuum being applied on the smallest nipple on the canister. Apply vacuum to that nipple and it should hold. If it doesn't hold vacuum, the diaphragm has ruptured and you need a new canister.

No.

Reply to
bllsht

Thanks Jerry,

I'm in a unique situation where I'm living in an apartment complex and my parking space on the side of the building is pretty much out of view when I park my other car behind it. I can do lesser stuff this way but I try to be real quiet with ratchet wrenches and stuff so my appt manager can't detect me working on my jeep. Actually, I can't believe I got this far (installed the MPI kit, put a 4" lift on it, dropped the gas tank and installed a new sender, pulled the head and now installing rings) but everything is against me with installing an engine. I'm not opposed to it, just that it would be too hard to conceal from my appt manager. Add to that I don't have a transport for an engine.

If I owned my own home I'd be on it real quick.

Bill

Reply to
William Oliveri

Understood. I am a recovering apartment dweller myself, and I can relate with having done a heck of a lot more in my parking lot than I probably should have.

Someone here ought to volunteer a little driveway time and help you out. Mine is available, if you wanna come east.

Jerry

Reply to
Jerry Newton

I have seen 4 new canisters and not one of them would 'hold' a vacuum on that diaphragm port.

Those are not a solid vacuum part, but have a leak down rate it would appear, something like some EGR valves.

That is why I couldn't offer any proper way to test them off the engine.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

bllsht wrote:

Reply to
Mike Romain

If they were leaking, they were bad. I've come across a few that were defective out of the box, but they are supposed to hold vacuum. It's a solid rubber diaphragm.

The test is straight out of the FSM.

Reply to
bllsht

That figures. They are a dealer only item and one of those leaky suckers is on my Jeep!

I got mine for less than $70.00 in 1999, then the pricks doubled the price in 2001.

Hmm, I wonder how long the warranty is for? I save receipts....

Mike

bllsht wrote:

Reply to
Mike Romain

One other quick check while it's hooked up. If the diaphragm has ruptured, you can feel vacuum on the signal nipple while the engine is idling, due to the manifold vacuum that's applied below the diaphragm. Since the ported vacuum to the canister is the same ported vacuum source for EGR operation, under some conditions, it could cause excessive EGR. Just a little trivia...

Not sure about the warranty >That figures. They are a dealer only item and one of those leaky

Oliveri"

Reply to
bllsht

That would be like pinching the tube to the manifold closed while idling. If the idle changes, it is toast.

I will give mine a check.

Mike

bllsht wrote:

Oliveri"

Reply to
Mike Romain

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