Yet Another Head Gasket Story

[Iceaxe]

Installed an SC, dropped the pulley to 2.8", installed a meth kit, did a long pull up Mt Rose to Lake Tahoe, and noted it was moving very slowly. Then heard some popping sounds. Then saw a massive cloud of white smoke. Used up a couple quarts of oil. Saw bubbles in the radiator reservoir.

Good times.

 

[Iceaxe]

Ugh. Looks like I'm looking at an engine rebuild...

Guys at the shop are suggesting a rebuild to take into account the higher boost (now at ~6 PSI) that I'm running. They are arguing that, with 240k, a head gasket job will likely be insufficient. That we'll need to do more than that once in there, given the mileage. And I'm no engine guy....

Uuuuugh.

 

[bajaphile]

Sorry to hear about that.

I would agree that while the bottom end might be ok right now, the added compression with SC and new top end job would most likely cause the bottom to fail soon. Not always the case, but if it were me, I'd do the whole thing at once.

 

[Iceaxe]

Thanks bajaphile. Helps to overcome the overwhelming sense of dread...

On the brighter side, I'm kind of hoping the machine shop will be able to discuss boring out the cylinders with me...

 

[cme4lyt]

FYI, if you stay with Toyota OEM pistons, you don't have many options. You can go .5 over or 1.0 over, that's it. The 1.0 over basically takes it to a 4.6 liter.

BENO, on the forum, can hook you up with both rings and pistons.

 

[Iceaxe]

Copy that- thanks cem4lyt. Beno helped me tremendously on the SC install.

 

[ton504]

Installed an SC, dropped the pulley to 2.8", installed a meth kit, did a long pull up Mt Rose to Lake Tahoe, and noted it was moving very slowly. Then heard some popping sounds. Then saw a massive cloud of white smoke. Used up a couple quarts of oil. Saw bubbles in the radiator reservoir.

Good times.

Long pull as in pedal to the floor under heavy load? Or just low gear high rpm cruising? Any egt, coolant, wideband info?

 

[Iceaxe]

The former rather than the latter. Coolant is dark, looks like it has oil in it. I did a diagnostic on it when I got home and was shocked to see NO CODES...!

Woke up this morning and drove it on the highway to the shop and it cruised at 65 MPH with no problems. But some smoke under acceleration before I got on the highway.

 

[scottryana]

Not sure what the engine rebuilders are suggesting?? More details would be needed. But I know when I pulled my head the cross hatches were still visible in the bores. I think it is slightly irresponsible of them to make any claims as to what you "need" before the engine is apart.

I agree that it would be nice to have a brand new fresh rebuild, but there aren't a lot of places I would trust with that work.

The pistons and rods will be totally fine at those boost levels, you might need new rings and fresh bearings but those do not constitute a complete rebuild.

Several things to think about. What head gasket bolts/studs will you use? If you are doing an in-chassis rebuild will you be able to get the block smooth enough for an MLS gasket? How much are you willing to spend on "while you are in there" projects? Do you trust the "guys at the shop"?

Good luck!

 

[Iceaxe]

scottryana, your comments are well taken... here's what was discussed:

Context. In Reno we have little direct access to TLC enthusiasts who have the kind of skills for this task. While I am certainly willing to tear into the head to replace the head gasket, I do have 240k with forced induction on an engine with an unknown history. The mechanic is a multiple-decade of experience hot rodder. The machine shop comes from a hot rod / old school background as well. Both well recommended for such work, however with the caveat that no one is a TLC specialist. And I don't trust the dealership.

What they suggested was the following:

• Because the engine is dated with an unknown history, they are proposing a rebuild is in its future. It is a matter of when, not if.
• Because the head gasket is toast (at least), they proposed to rebuild the engine from the bottom-up with new rings, bearings, etc. Granted, I did inform them the engine can handle the higher pressures.

The truck is being gone over now to assess the true level of damage. The mechanic is concerned they will pull the head and discover other issues or not discover them, replace the gasket, then have the engine fail later down the line when a rebuild is necessary anyway (except I'd be out a few grand for the head job).

So, damned if you do / don't kind of situation.... with unknowns and an owner who is not adept at pulling apart the engine (nor with hands-on experienced assistance out here to DIY).

 

[NickPsy]

Iceaxe-

I feel your pain, I'm essentially in the same place you are. Blown HG on my rig and faced with the potential of more problems once they start on the repairs. I don't have the time or confidence to attempt the head gasket repair in my driveway so I'll eventually bite the bullet and have it repaired . Good luck with whatever you decide and keep us posted.

Nick

 

[LFD2037]

Just an FYI, old hot rods and the 4.5L are way different animals. I'm from the hot rod class and these things are quite different. Sure, they're both internal combustion but that's about where the similarities end.

 

[dogfishlake]

Sorry to hear about the bad luck. Sounds like you will be turning this in to a positive by making the truck better than it was before. There is an excellent chance that upon teardown, your machinist will find things in good shape tolerance wise and really need just a bearing refresh. That would help with cost quite a bit. It's a good opportunity to catch "while in there" stuff, and maybe go for an mls gasket and head studs (not necessary but top shelf). Good luck!

 

[Iceaxe]

Thanks guys for the encouragement. I'm a bit more positive and hopeful this am after sleeping on it.

 

[OGBeno]

Whatever you do, do it once and do it correctly. Don't dick around with trying to cut corners or save $5 on a $5K engine rebuild. Not worth it in the long run considering how much you have already invested in the SC.

 

[Iceaxe]

beno, totally agree. I'm hoping this is the one and only time I ever have to do this....

 

[Iceaxe]

Ok, now I'm in a state of confusion. The guys pulled the plugs and took a good look inside, and apparently found non-clean cylinders, nothing unusual, no evidence of gasket compromise. They suggested the SC was responsible for excess oil getting sucked into the intake and bogging the engine down (???) No codes on the engine. The truck did drive fine heading down to the mechanic...

Is it possible the SC is responsible for oil bypassing the rings?

 

[Iceaxe]

I wanted to cap off this thread...

"Final" diagnosis: not the HG, but rather a combination of a never-replaced PCV and need for an oil catch can. Indeed the rig was thriftily sucking oil right into the intake, bogging it down on long hill climbs and causing it to spew smoke.

• I noticed immediate improvement on the hills once I installed the oil catch can, and yes it catches about a teaspoon of oil during long mountain climbs.
• When I replaced the PCV, my brakes were noticeably different (an indication of increased vacuum to the brake booster), as well as noticeable improvement in engine responsiveness and performance on hills.

Problems appears solved (for now). Acknowledged, there could be an unseen problem somewhere in the engine, but I've not see it yet (knock on wood).

Dumb Ass Moment (DAM) #5,475.

 

[DARKNESS]

You may want to consider this:

PCV 101 for Forced Induction 80's

 

[Jason hansen]

I have heard of head bolts stretching under load and oil getting into the coolant. I happened to my brothers race car.