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Discussion Starter · #1 · (Edited)
I've been jacking around with a rough idle for a little while and after cleaning the throttle body, changing plugs and O2 sensor, I put the gauge on it. I've got 115# on number 3 and +/- 200# on the other 5. I also have a sound that is similar to a small exhaust leak - kind of has that tap sound like an exhaust leak (though I know it isn't exhaust that is leaking).

I've read a few other threads about bad heads, cylinder liners etc and the costs are pretty frightening. With 93,000 miles, I am also facing a bad wheel bearing , sway bar end links, brakes, belt, transmission service and the other preventative measures you would take when approaching 100K. All of that will add up to quite a bill in itself.

Trying to decide whether I should just try to dump it. What do you think-Is there any chance at all that I could luck up and this would not be as significant as the $3000-$4000 head repairs I've been reading about?

:(Thanks
 

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Discussion Starter · #4 ·
Thanks roadie and lis. I did find one on part.com I think I will have shipped from Arkansas. The guy told me someone brought theirs in for a rough idle and it had a burned valve. He sent it to a machine shop for a valve job. In the meantime, the owners aftermarket warranty paid for a new engine, so he put him an engine and stocked the serviced head when it returned. He wants $35o for it.

As suggested in another thread, I put a little oil in the cyl and rechecked the compression and got the same result, ruling out the rings. Is there anything else that would cause low compression that's not part of a complete head assembly? I can't think of anything else, but obviously I'm not a mechanic. Another question I have is: Is there any characteristic of a head that burned a valve once, that would cause it to do the same thing again? In other words, with the head mentioned above, would it be likely to repeat since it did it once already(once a bad head always a bad head?)? Or does it not work that way with this?

Thanks again guys
 

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I put the gauge on it. I've got 115# on number 3 and +/- 200# on the other 5
but obviously I'm not a mechanic
dont lie:D

o When the compression measurement is normal, the compression builds up quickly and evenly to the specified compression on each cylinder.
o When the compression is low on the first stroke and tends to build up on the following strokes, but does not reach the normal compression, or if the compression improves considerably with the addition of three squirts of oil, the piston rings may be the cause.
o When the compression is low on the first stroke and does not build up in the following strokes, or the addition of oil does not affect the compression, the valves may be the cause.
which best matches your test results?
 

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Discussion Starter · #6 ·
May- If you only knew....I've got a socket set and a small bag of rusty tools. I will say this, you'd be surprised how much you can do with so little. Check out the pic of my complete mechanic's shop. That's all I got - seriously!

To answer your question, definitely #3. With a tablespoon of oil in from the top, I get no improvement at all.

Another note- August the TB will make 5 y.o. and currently has 94,000 miles. Every drop of the original coolant is still there, so I cannot see it being a head gasket issue.

With that said and therefore assuming it is valve related, would you recommend having mine repaired, or paying the $350 for another refurbished one and having it swapped out?

Either way, I don't think my "garage" is equipped to handle this at home.:rotfl::rotfl::rotfl::rotfl:


Many thanks:tiphat
 

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May- If you only knew....I've got a socket set and a small bag of rusty tools. I will say this, you'd be surprised how much you can do with so little. Check out the pic of my complete mechanic's shop. That's all I got - seriously!

To answer your question, definitely #3. With a tablespoon of oil in from the top, I get no improvement at all.

Another note- August the TB will make 5 y.o. and currently has 94,000 miles. Every drop of the original coolant is still there, so I cannot see it being a head gasket issue.

With that said and therefore assuming it is valve related, would you recommend having mine repaired, or paying the $350 for another refurbished one and having it swapped out?

Either way, I don't think my "garage" is equipped to handle this at home.:rotfl::rotfl::rotfl::rotfl:


Many thanks:tiphat
thats more tools then i have *shiftey eyes* i swear...

if u were doing it urself i would say just go get a new head.. but if ur gunna take it to a shop to do it one way or the other... i would take it to a shop that u trust and ask them to take a look at it and see if htye come to the same conclusion u hav... and if so ask them what would be easier/cheaper... having them fix the current one or getting another head and just replacing it for u...
 

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Discussion Starter · #8 ·
Hatchet,

A shop I can trust....never heard of such a thing.

My neighbor however has a transmission shop and I have had a few things on other vehicles fixed by him with mixed results. I feel pretty good with them doing the head swap, but not so sure in his ability to properly assess my head and properly determine which is the better route.

Seriously, would you try doing the swap yourself?

I'm game if there is a reasonable chance I can get through it. What other jobs would you compare it to difficulty-wise that I may have done before?

Do you know what else has to be disassembled from the head? Do you have to undo the exhaust manifold?

I told y'all I wasn't a mechanic!!!

I have changed an exhaust manifold gasket on a 4 cylinder and drilled/tapped and put a s.p. thread insert in the head of that Toyota in the pic.(in place because I didn't have a special tool to break the nut on the cam shaft/timing belt pully to pull it)

Now that I think about that, I better leave it to more capable hands...
 

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May- If you only knew....I've got a socket set and a small bag of rusty tools. I will say this, you'd be surprised how much you can do with so little. Check out the pic of my complete mechanic's shop. That's all I got - seriously!

To answer your question, definitely #3. With a tablespoon of oil in from the top, I get no improvement at all.

Another note- August the TB will make 5 y.o. and currently has 94,000 miles. Every drop of the original coolant is still there, so I cannot see it being a head gasket issue.

With that said and therefore assuming it is valve related, would you recommend having mine repaired, or paying the $350 for another refurbished one and having it swapped out?

Either way, I don't think my "garage" is equipped to handle this at home.:rotfl::rotfl::rotfl::rotfl:


Many thanks:tiphat
Look at the bright side, its easy to keep things organized!:cool:

I've spent the last ten minutes searching for the cylinder leakdown procedure but unfortunately I cant find it at the moment...

Assuming it is a burned valve and the head is salvageable, I would have the valve job done. Although it will cost a bit more then the used head, you'll know who had their hands in it and who to see if something goes wrong (knock on wood). The chances of any support if there is a problem with the used head are slim to none.

I've done a few head gasket jobs in the drieway but i dont think i would do one of these I6s without a hoist...it looks heavy:ugh:
 

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:m2: I would consider buying a complete used engine. Maybe a little more for parts, but what I've read here, replacing the head on the I6 is VERY labor intensive.

I'd also say, unless you are an experienced mechanic I don't think replacing the head on an I6 is a job for a D.I.Y. The few people that have had this same problem have said that the head wasn't fixable. I'll see if I can find the links and post them.


Edit: Here's the only one I found so far.

http://forums.trailvoy.com/showpost.php?p=701878&postcount=23
 

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Discussion Starter · #11 ·
Again, much thanks guys.

I remembered the name of a guy that a friend recommended and I have even met when he put a new engine in my friends truck. I do remember him seeming trustworthy and seeming to really have his act together. I think I'll let him take it down and give me an assessment.
 

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Discussion Starter · #13 ·
Just curious, what's the risk in putting this off a while? Other than the rough idle, it operates fine. Others who ride with me aren't even aware something is wrong. Will I damage something if I don't make this repair right away?
 

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Seriously, would you try doing the swap yourself?
At home? Absolutly not. You will need the special tool to hold the timing chain (if that falls off you're f*cked) and the knowledge of the engine (like that you WILL break at least one head bolt). I would highly recommend you get this done at a dealer. They will have the special tools and knowledge to get the job done right. Plus, they will be able to get you a brand new head, not a used part.
 

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At home? Absolutly not. I would highly recommend you get this done at a dealer. They will have the special tools and knowledge to get the job done right. Plus, they will be able to get you a brand new head, not a used part.
Spoken like a true company man!!!!!!!!!!!!!!
 

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Spoken like a true company man!!!!!!!!!!!!!!
Uhh, yeah... I'm all for DIY, but this is not something that one should attempt in the driveway in my opinion, at least not without the special tool for holding the timing chain and definately not with only having a small bag full of tools. Not saying it couldn't be done in the driveway, but you'd better have the experience and the right tools. Hell, I've done two of these and I would not want to do it in the driveway without a lift.
 

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Discussion Starter · #18 · (Edited)
Guys,

Don't worry. I ain't trying that in the driveway. I have dealt with broken exhaust manifold bolts in the head before. But that was on an old, secondary vehicle. I am quite a bit more cautious with the family wagon and not so brave (or insane if you prefer).

With that decision out of the way, now I want to know how long can I go with it as is before getting it done? 3-4K is quite a hit. Will prolonged use cause further damage?

OH,
They will have the special tools and knowledge to get the job done right.
That's not a given. My dealer broke their tool changing my ball joints and I was without a vehicle for a whole weekend and they ended up borrowing a tool from a GMC dealer in town to finish the job. They couldn't change the a/c controller on the first try either. That's when eveyrone at the place became very aware of my opinion of them. If you're a good dealer tech, I wish you were at my dealer. Please understand my lack of fascination with the whole "dealer" thing. I do think you are better off at the dealer when it comes to handling re-work. But getting it right the first time, I haven't seen it.
 

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I would say probably not, because it seems the problem is just a leaky valve. The spark plug is still going off so most of the fuel should still be getting burned, that's the only thing I would worry about since raw fuel is no good with the cat.
 

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Discussion Starter · #20 ·
Got an estimate

I was recommended a "good trustworthy mechanic" today. As much as you can tell over the phone, he did sound like it and I got several reliable references from personal friends. I called and talked to him and according to his formula, his preliminary estimate was around $800 parts/labor. He did caution that we would be at the machine shop's mercy once they got the head and that unusual repairs could increase the bill.

I am prepared for it to be more than that estimate. But from the numbers ($3000-$4000) I have gotten from others on here, I almost feel like something has got to be missing. Any ideas on what may not be accounted for in that $800 estimate?

Oh, in an apologetic way, I did get it off my chest, when I talked to him, the point about the timing chain. He acknowledged it, but is there a good clear description I can give him about why this situation is unique?

Thanks again
 
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