HG replacement failed, need ideas

[zukatude]

After spending 20 odd hours replacing the HG on my 94 (140k miles), its no better. Got it started last night and it still blows white smoke and I can clearly see bubbles coming up in the coolant overflow. I was so mad I could throw a wrench through its windshield.

The cylinder head was checked out by Mountain High Performance in Arvada, Colorado. Here's what they did:

1) Clean & grind valves/check guides, springs, valves for wear. All ok and reused. Reassemble with owner provided valve seals.
2) Straighten cyl head warp on head surface of .025"+. Less than .012" after oven, cams now turn by hand.
3) Adjust valves. Clean camshafts, followers, all cam caps. Torque cams into place. Select adjust each valve. Disassemble and re-clean.
3) Resurface cyl head .017".
4) Boil intake manifold, cams, all apparatus, rocker cover.

All this plus shop materials (cleaner, lube, paint, etc) was $627.50. The gasket kit and misc PM parts from Dan was another $231.

At this point I'm not sure what do. I have a local independent toyota mechanic that I've have good experiences with before, but he tells me that he has never done a HG on a 1FZFE before. I'm afarid to just hand it over and then find out later that something is cracked and needs a new cylinder head or block. I hate to get rid of it now as its not worth much not running (bought it for $10k two years ago when it had 125k miles). On the other hand I just want out of this POS and to move on to something more reliable.

Any advice out there?

Thanks for your help,
Paul in Windsor, Colorado

 

[FJBen]

Hey Paul! nice too see another 80 owner in Northern Colorado!

That sucks, I"m not sure when Robbie gets off his tour of duty but there is an option as well as Slee for that work. Don't know of anyone local around this area that knows the 80 series HG's...

 

[e9999]

sorry to hear that.
didn't the shop check for cracks?

could this have to do with insufficient tightening of the head (wild gratuitous guess)?

 

[RavenTai]

how long did you run it?

after having the cooling system open it will burp bubbles for a wile as air pockes are displaced by coolant, others have also reported white smoke after HG job due to leftovers in the exhaust, both of these should clear up with time,

 

[zukatude]

sorry to hear that.
didn't the shop check for cracks?

could this have to do with insufficient tightening of the head (wild gratuitous guess)?

Yes, they saw no cracks or evidence that the head could not be reused.

As far as tightening of the head, I have the FSM and followed it closely. First pass is at 29 ft-lbs, then turn 90 degrees, then another 90 degrees.

How to know if its the head or block? I suppose the only way to know what went wrong, is to pull the head again and send the whole pile, truck included, to the shop

 

[97fortieth4me]

Wow! Sorry to hear about your HG.

Did the machine shop pressure test(cracks) the head when they had it?

A friend & I finished my HG last Friday evening with no issues.

 

[zukatude]

how long did you run it?

after having the cooling system open it will burp bubbles for a wile as air pockes are displaced by coolant, others have also reported white smoke after HG job due to leftovers in the exhaust, both of these should clear up with time,

I only let it idle for about 5 minutes to warmup. It puffed out significant amounts of white smoke the entire time. It also has a miss and stumble upon accell and decell from idle, just like before. At first the idle was pretty quiet and smooth, but after a couple minutes it became more ragged.

 

[stanley]

block cracked?

 

[NeverFinis]

You still might not have a blown HG......

1) You might have air in the cooling system.
2) You might have coolant in the exhaust from previous blown HG.

Run the engine some more...let it get hot but watch the guage.

Leave the radiator cap off while you do this.

Does the bubbles increase if you rev the motor?

Oh, check the oil cap for white residue...but again, you might have coolant still in the engine due to the previous HG. If there is white residue, let the engine get hot and then do another oil change.

 

[zukatude]

You still might not have a blown HG......

1) You might have air in the cooling system.
2) You might have coolant in the exhaust from previous blown HG.

Run the engine some more...let it get hot but watch the guage.

Leave the radiator cap off while you do this.

Does the bubbles increase if you rev the motor?

Oh, check the oil cap for white residue...but again, you might have coolant still in the engine due to the previous HG. If there is white residue, let the engine get hot and then do another oil change.

I really hope its not blown, but as I mentioned above, the idle is ragged and stumbles on accelleration and decelleration. Which is the same symptom I had prior to the HG replacement.

 

[NeverFinis]

You can run your engine for a bit and then pull the spark plugs and inspect them. Did you check the old HG to see where it failed?

Ok, determine if it is fuel, air, or spark is causing your stumble...

Determine which cylinder is missing by pulling spark plug wires. Check your timing, and make sure your wiring harness isn't damaged, especially in the back where it makes that bend. Make sure the injectors are firing by listening to them making clicks.

 

[wsdavies]

I feel your pain man..there is no more frustrating a feeling as you get when something you worked hard on takes a dump, and there's no obvious reason why..that and not being able to find car keys when your already late to work. My HG went bad a couple of months after getting my 80..so I know how you feel...

 

[DaveyBoy]

I really hope its not blown, but as I mentioned above, the idle is ragged and stumbles on accelleration and decelleration. Which is the same symptom I had prior to the HG replacement.

When disconnecting the battery, I think it take several
restarts for the computer to "learn the engine.

Hope that helps.

 

[zukatude]

Wow! Sorry to hear about your HG.

Did the machine shop pressure test(cracks) the head when they had it?

A friend & I finished my HG last Friday evening with no issues.

97fortieth4me,

How did your rig startup after the new HG? Did it run poorly for a while or did it just fire up as if nothing bad had ever happened?

TIA

 

[Atticus]

When disconnecting the battery, I think it take several
restarts for the computer to "learn the engine.

Hope that helps.

X2. Your rig will run roughly for a while after you disconnect the battery. After doing all that work, I'd at least run it for a while to make sure the hg job didn't "take" before I threw in the towel.

If you've got a cracked block, what more damage are you going to do?

 

[hks3sgte]

block cracked?

x2!

 

[97fortieth4me]

97fortieth4me,

How did your rig startup after the new HG? Did it run poorly for a while or did it just fire up as if nothing bad had ever happened?

TIA

It was hard to start up and the idle was low after the initial assembly. It was because it was off 1 tooth. After we got it all back aligned again and it fired-up with no problem.

The best way to describe it was, remember that old Infinity or Lexus commercial BITD, where they were trying to show you how smooth the engine was? They had a glass of wine in the engine bay? Anyway, it was soo smooth that I thought of that commercial instantly. We left the rig alone 'til the next night. We changed oil; topped of coolant; & set the timing the following night. Now, she runs really strong.

 

[cruiserman]

25mils of warpage? Wow. 17mils is a lot of aluminum for surfacing. I imagine your compression ratio went up some.

 

[IdahoDoug]

Agree - don't give up on it so quickly. The white smoke could be leftover coolant in the exhaust, and the bubbles would be expected until the cooling system purged itself of air. Try driving it around (with a gallon of premixed coolant riding shotgun) and watching the temp gauge.

The rough idle could be either the map relearning, or you've coincidentally got either an injector or a spark plug not connected fully. For instance, after I got my fuel rail back on, I inspected each O ring with a bright flashlight and found that one had not seated correctly. Would have been a rough runner had I not found that. Don't go looking on yours for it - just pointing out that a minor thing like that could be your issue.

So, run it around being sure the rad/overflow are full (overflow will get sucked dry sometimes as engine purges its trapped air) and watching the temp guage.

As the only forum member here do to a HG and days later pull the head back off due a crack, I feel your pain and frustration. Mine was far worse - ran fine but continued to suck water so I had no new symptoms to guide my search.

DougM

 

[Gumby]

I think yer OK. Your cat probably has a bunch of coolant in it. Your ECM has reset and you have to run it a while to get all the air out.

as has been stated previously.

I have also seen a cracked throttle body misdiagnosed as a bad head gasket. The coolant passage in the throttle body was cracked and leaking coolant into the intake.

Your intake would have coolant in it if that was the case.