Good reason to change headgasket before it blows

[Devil's Slide Doug]

Do they still show pictures of bloody victims of traffic accidents to scare new drivers into safer driving? Well here is the headgasket version. :whoops: By now, everyone should know to change their headgasket. I am the third owner of a 1993 fzj80. I bought it with 146,000 miles. The previous owner provided receipts of maintenance and a new radiator, etc. I have kept fresh Toyota Red in the radiator. At 198,000 miles I had a major head gasket leak in the 4th cylinder. (lots of steam/overheating and hydrolocked cylinder) I figured I would deal with it when it happened. Now I am dealing with it and it is not as simple as just cleaning off the block and getting the head machined and then slapping it back together. Serious pitting and etching from the fire ring. I don't know if this could have been avoided by changing the gasket several years ago but waiting this long means a lot more work since the block now needs to be decked big time which is a lot more work. The question is can a block/timing chain cover be successfully decked close to .5 mm? I have to choose 1 of three options.
1.Used engine to freshen up (change the head gasket) and install
2. Have a lot "skimmed" off the block and use a custom thick cometic gasket. (This also means new bearings/rings/seals while I am at it since the block has to be completely stripped down).
3.New oem short block (plus new oil pump and timing chain and guides and parts that would be stupid not to have be new at that point).
While I am saving my pennies for the above options I will put it back together and see what happens. How long till it blows again? Here are some Photos of cylinder 1 which is the ugliest and clearest photo and some gratuitous shots of the blown gasket.

 

[Devil's Slide Doug]

#1 about to go, had been leaking for a while



#6 about to go, had been leaking for a while



#4 Blew out big time.

 

[Tenzig Norgay]

I saw your earlier pics and all I could think of was that your screwed. Can't believe no one has seen this before and chimed in on solutions, but I kind of liked the skim coat with JB weld solution then resurface. Looks nasty and I doubt slapping it back together will work, but I know little when it comes to this sort of thing.

 

[BrotherRob]

So this would have been more acceptable if it happened to your second head gasket?

 

[Devil's Slide Doug]

So this would have been more acceptable if it happened to your second head gasket?

I probably was not clear. My point was that If I had changed the head gasket earlier I may have prevented the etching/pitting caused by by the prolonged use of the failing gasket.

 

[BrotherRob]

I probably was not clear. My point was that If I had changed the head gasket earlier I may have prevented the etching/pitting caused by by the prolonged use of the failing gasket.

May have......maybe not.

Something odd happened here, you may not have been able to prevent it. I'm guessing your head was warped or the block or head may even have a manufacturing defect. Had you changed the HG earlier, you may or may not have caught the problem.

Look at the bright side, you could be doing the job a second time, then you'd really be pissed.

 

[1973Guppie]

is the block warped? I guess I am missing something? I would think getting the head redone and a new headgasket and you should be just fine.......

 

[1973Guppie]

sorry, just reread the hydrolocked cylinder.....

did you drive on it for awhile after it blew? usually you know when they blow and you can stop driving them (ie: major power loss), just curious how the engine seized up so quickly?

 

[B Legit]

How do the cylinder walls look? if they do not look good, I would not put any more money into that engine. Find a decent used one, do the HG on a stand rather than in the truck and plop it back in. My block looked about as bad as yours did when I put it back together pluss I had some minor scoring on the cylinder walls and pre ignition damage on the #1 piston head. I put it back together and it ran ok with some minor power loss, but almost immediately started an external water leak between the #5 and #6 cylinder. Should have just called it right there and dropped in a new engine. If you can muster the dough for a new short block and your head is reconditioned you should be good to go. Have you had your head at the machinist yet? That would help you decide how deep you need to reach.

 

[CycloSteve]

Based on the pics, this is one of the most pitted blocks I have seen. The two of the three rigs which Robbie did at my place were done as PM's, and though the gasket rings were deforming, no permanent damage had yet occurred. All three were in the 150-175k mile range, and you could see the impending doom.

Now I don't feel so bad about my original HG blowing at 94k miles. When we had it back apart at 150k miles, due to the secondary issue of a cracked head, the block did not have any noticable pitting. Basically the PO installed the S/C, and blew the HG within a month IIRC. They replaced the HG, but nothing else which made for a fun 2nd HG job.

So, Doug, I guess you are not heading up to Wentworth Springs this weekend...will have to plan another run when the truck is back to life, perhaps in September before the weather turns. I will be up there, but doing a number of different day trips to various lakes for some fishing.



Steve

 

[Devil's Slide Doug]

Head has already been resurfaced, valves adjusted etc. So the top end is good to go. A used motor will likely have as as many miles on it and be a crap shoot and will at the very least need a new head gasket. If I have my block decked, I will rebuild it while I am at it. I will be paying for machine work and bearings/rings/pistons and seals and I honestly don't have the expertise to verify that work so I will have to pay more for a mecanic/machinist's labor. I have a feeling that it will start to add up in price and may still be not quite right. So,as a temporary "fix" I will jb weld the etching/pitting , (by the way, this is a factory approved repair according to a defunct car company called Saab) Bentley Publishers - Technical Discussions : JB Weld on a block surface !!! ??? M30 .... This MAY buy me a little time while I save some pennies to purchase a new short block (and a few more parts), acquire an engine stand, rent a hoist, clean the garage and prepare to do it right. I will be able to juggle car parking spots in my crowded neighborhood and use the Cruiser for grocery getting and keep my AAA up to date. So yes I will be doing a second head gasket within the next year (hopefully before it blows again) but at least I will have had some practice doing it.

 

[Devil's Slide Doug]

So, Doug, I guess you are not heading up to Wentworth Springs this weekend...will have to plan another run when the truck is back to life, perhaps in September before the weather turns. I will be up there, but doing a number of different day trips to various lakes for some fishing.



Steve

I will be bolting the seatbelted jump seat back into the mini truck for kid hauling until the Cruiser is running again. I may hit the trail in the mini truck but am a bit leery about taking the Cruiser on long trips to remote locations. (I already used my 200 mile AAA tow so I only have some 100 mile tows left for the year.) Basically I will drive it about as far as I would drive an electric car. A whole new meaning to "range anxiety"

 

[Devil's Slide Doug]

sorry, just reread the hydrolocked cylinder.....

did you drive on it for awhile after it blew? usually you know when they blow and you can stop driving them (ie: major power loss), just curious how the engine seized up so quickly?

I stopped driving, the motor sucked coolant into the cylinder after it was shut down and cooling down.

 

[elhombre]

How much was shaved off the head? Add that number to the amount you figure that will have to be shaved off of the block. You may be getting to a point where the compression will signifigantly increase and the engine will require high octane (race fuel) gas to run without pre-ignition. I don't know the numbers which you must become concerned with but it should be considered.

I vote short block, but I am the kind of guy who stayed up thinking about the head gasket before I replaced it.

 

[Devil's Slide Doug]

How much was shaved off the head? Add that number to the amount you figure that will have to be shaved off of the block. You may be getting to a point where the compression will signifigantly increase and the engine will require high octane (race fuel) gas to run without pre-ignition. I don't know the numbers which you must become concerned with but it should be considered.

I vote short block, but I am the kind of guy who stayed up thinking about the head gasket before I replaced it.

.009 was shaved off the head. That is one of the reasons why I am leaning towards a new block. If I were to reuse the block I would be using a custom thickness cometic head gasket.

 

[B Legit]

Head has already been resurfaced, valves adjusted etc. So the top end is good to go. A used motor will likely have as as many miles on it and be a **** shoot and will at the very least need a new head gasket. If I have my block decked, I will rebuild it while I am at it. I will be paying for machine work and bearings/rings/pistons and seals and I honestly don't have the expertise to verify that work so I will have to pay more for a mecanic/machinist's labor. I have a feeling that it will start to add up in price and may still be not quite right. So,as a temporary "fix" I will jb weld the etching/pitting , (by the way, this is a factory approved repair according to a defunct car company called Saab) Bentley Publishers - Technical Discussions : JB Weld on a block surface !!! ??? M30 .... This MAY buy me a little time while I save some pennies to purchase a new short block (and a few more parts), acquire an engine stand, rent a hoist, clean the garage and prepare to do it right. I will be able to juggle car parking spots in my crowded neighborhood and use the Cruiser for grocery getting and keep my AAA up to date. So yes I will be doing a second head gasket within the next year (hopefully before it blows again) but at least I will have had some practice doing it.

Well, you might be surprised what you can find. I found a local shortblock in pristine condition within a week of searching that needed an HG and already had the head off. I certainly wouldnt suggest buying an engine from a junkyard and crossing your fingers but you have some good resources in California that could possibly set you up for a lot less money than a rebuild. Give Georg at Valley Hybrids a call and see if he has anything for you. I think that removing the engine you have, and paying to have all of that work done to it will yield less benefit than just buying a short block with our generous mud discount at American Toyota. It would be a total bummer if your known to be sketchy block took your newly refreshed Head to hell with it when it decided to give up the ghost though. Just money down the drain imo. I know where you are as I was there just last year. Hope you get it sorted man.

 

[1973Guppie]

do a toyota v8 swap, more power, keep it toyota, etc. I plan to do this someday to my 80.....

 

[Schwaz80]

Forgive my ignorance. What is a short block?

 

[Offroads4x4]

Short block (Block, Pistons and rings, Crank and bearings, new freeze plugs) basically everything below the head. Long block includes the head valves etc..
You still have to swap over things like A/C, Alt, Oil Pan, brackets, motor mounts, exhaust and intake manifolds .......

 

[hawaiicruz]

Forgive my ignorance. What is a short block?

an engine minus the head