Head gasket--slightly rough block (1 Viewer)

[ralphy1997]

I've been replacing my head gasket all summer as time and mostly money permits. I was leaking at #6 and the gasket finally blew there. I have my rebuilt head back from the shop and was giving the mating surface on the block one more pass with the gasket scraper before attempting to mount the head. All of the mating surface is completely smooth, except for two spots on the back of #6 that still feel like they have gasket on them. Upon closer inspection, it looks like the surface is slightly rough and that it's rough because the surface has worn. I'm not sure if I was too aggressive with the scraper (possible but I wasn't pushing very hard) or if the leak from the headgasket corroded the surface, leaving it uneven.

My question is this: how worried should I be? How much "roughness" on the block will the head gasket make up for? Should I try a sealing product around that cylinder when installing the HG? I have pictures but you can't really see the problem--it's more of a feel thing than a see thing. By feel, it's not super rough, but enough that you can tell the difference.

What thoughts/opinions do you have?

 

[Kernal]

Can you take a few photos and post them up?

 

[ralphy1997]

Can you take a few photos and post them up?

Hard to see anything in the pictures but here you go. . .

The first is cylinder 6. The spots I am talking about are at about 11:00 and 1:00 on the surface (between the triangle ports and the cylinder.

Second pic is the right side--tried to get a profile shot (this side is the worst) and the third pic is a close-up of the left side.

As I said, the pictures don't seem to help too much--it's more of a touch thing than a see thing.

 

[Kernal]

You might try taking your photos from a bit further back but using zoom, manual focus, and experimenting with different angles to get rid of the flash reflection IMHO. Wait for the headgasket experts to chime on how to deal with the erosion.

 

[BlueWithNV]

Block imperfection

I had the same thing. My mechanic said it was electrolysis from the aluminum head mating with the cast iron block. I think it is more prolific in the southwest, but is related some degree to the minerals in the water that you put in the radiator (have you ran distilled water?) With mine he said he could put it back together and it might last 5000 miles or 50000 miles. Beings it had 182 k on it I chose to buy a new block to remain within specs with a milled head. Cross hatching on the cylinder walls still present.

If you want a very rebuildable block that includes the crank and pistons, i have one in my garage in a toyota crate. You can have it if you pick it up in New Meadows/ McCall, just email me at rrichards3894@gmail.com. I work for the US Forest Service.

Russ

 

[ralphy1997]

I had the same thing. My mechanic said it was electrolysis from the aluminum head mating with the cast iron block. I think it is more prolific in the southwest, but is related some degree to the minerals in the water that you put in the radiator (have you ran distilled water?) With mine he said he could put it back together and it might last 5000 miles or 50000 miles. Beings it had 182 k on it I chose to buy a new block to remain within specs with a milled head. Cross hatching on the cylinder walls still present.

If you want a very rebuildable block that includes the crank and pistons, i have one in my garage in a toyota crate. You can have it if you pick it up in New Meadows/ McCall, just email me at rrichards3894@gmail.com. I work for the US Forest Service.

Russ

The electrolysis explanation makes sense. Before I bought it, I know the truck lived in Colorado for some time--not sure if that's Southwest enough. . .

Thanks for the offer on the block. I'm not sure I'm ready to tackle a block rebuild right now from a time/money standpoint.

I'm thinking of using a coating of FIPG on those spots--the FSM calls for it up front, so I'm assuming it will handle the heat and the pressure if I apply it there. I wonder if this would be a problem? I know it would be a bandaid but it seems like it might be a pretty good one.

 

[Devil's Slide Doug]

https://forum.ih8mud.com/80-series-tech/600569-good-reason-change-headgasket-before-blows-3.html

 

[Rwhat]

I dunno if FIPG is the best thing to use since it meant as a gasket sealer. IIRC people have used a 2 part epoxy weld. I think that's what Douglashuft used and other people also.

How is the cross hatching on the cylinders? In the picture it's had to tell, but 6 looks very shiny. Did you drive it for awhile with the gasket blown?

 

[Offroads4x4]

FIPG is not meant for that application and will blow out. Its more of a RTV type product.

I would research JB-Weld or a 2 stage epoxy like Liquid Steel for your application of a quick fix. There have been many who have used this on the head to make up for low areas. You may want to talk to a machine shop for their input as well.

I would use a die grinder and ruff up your surface if you go this route. Then apply the epoxy of choice and sand it down smooth and reassemble.

JM2C

 

[Devil's Slide Doug]

I have put about 6k miles on my jb weld repair so far. Daily driving, High speed freeway trips, towing a trailer in 100 degree weather with ac on and rock crawling. So far it is holding,"knock on wood". It is running great, no loss of coolant, no overheating, no oil consumption. I might just just drive it till she blows and then I will order a short block.

 

[swampfoxSC]

JBweld and let the gasket do the rest. If you dont want to deck the block. Gaskets are there help mate slightly irregular surfaces.

 

[fj4068]

I'd be tempted to put some Hylomar Blue on the block and gasket and call it a day. Permatex Item # 85249.

 

[Kernal]

Hylomar is a non-setting gasketing compound.

 

[Devil's Slide Doug]

I flipped a coin between hylomar or jb weld. If I had been able to just walk up and buy a tube I may have gone the hylomar route. The branding and distribution was a bit unclear to me at the time.