Hi,
i’ve got a repeat head gasket failure.
the previous owner told me he had a head job done. A few months in, the head gasket blew - a blowout on the top of cyl 5. One of the head bolts had stripped... so I repaired with a timecert and installed new gaskets.

Now, over a year (15k miles+) later, it blows again. Same location. The repaired threads are good.

It might be a surface defect (I did not get the heads resurfaced last time). There had been some minor pitting damage that I filled with JB Weld.
I fear it might be internal damage - I read about failures in the block behind the sleeve.

any advice on figuring out what to do?

Block: (I will scrape it to see what the surface is like)

Head:


Now that I look at it, the repair was on the top bolt between 3-5 right in the middle. Looks like it might have loosened (although at removal it was very tight), or like I said maybe collant seeped in through there; there may be internal damage in that hole.

what comes next?

Also, I have a single valve that is brownish. Anything to worry about there?

thanks!

 

Check the heads..They may not have been resurfaced the first time.

 

If the failure is in the same spot that was filled last time, that’s probably your problem. Or since they were not resurfaced, the head may not be flat.

Send the heads to a shop to check and deck. If that doesn’t remove the pitting, find a used set.

 

and get a flat bar and a feeler gauge and check the block surface too......

 

yep that’s it, i can fit a 0.003 in feeler gauge on the block right where the blowout was. The head is strait aside from minor pitting.

Any chance I can sand that guy down a bit? I’m not excited about the idea of taking the whole thing out & apart to get the block decked... plus if i’m at that point i’d get upgraded sleeves in and all sorts of other things... boy oh boy.

Edit: then again, 0.003 is not much - what’s the tolerance on that? I guess the gasket can take a bit, but since it’s localized it may not help...

 

Maximum head warp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.05 mm 0.002 in., would be the same or less for the deck.......obviously otherwise at max they'd be .004 apart. By the way that's the largest hg leak I've ever seen on a Rover motor and I've done several. Wonder if there was some sanding done on the original job. See if you can find another motor or at least a long block locally. Cheaper than a total rebuild and would be faster turn around.