Exhaust Manifold Gasket

Post by **Ian** » Wed Jun 13, 2007 11:47 am

Received at Bongo Towers. Can anyone help?

"I am having an exhaust manifold gasket nightmare. We had the characteristic screaming noise and drop in power at start up in December and had it replaced at AVA leisure. Three months later and it all started again. AVA tightened it which worked for two days but eventually redid the job, reboring the exhaust and replacing all the studs. Now after a month it's happened again and we are back with a screaming bongo. Any ideas? We have twice heard a two clunks from underneath before the screaming starts up. Grateful for any clues. AVA have been great and split the cost for the last job with us but didn't have any clue as to what was going on. Many thanks."

mikeonb4c · Post by **mikeonb4c** » Wed Jun 13, 2007 12:33 pm

I'm no techie but wouldnt this fit with the manifold being warped and needing skimming. The manifold bolts are tightened with the new gasket and manage to restrain the warped manifold for a while, before they give up (bang). The gap reopens and the whistling restarts, the gasket burns out.

But if this is the case, I would heave expected the garage to check the manifold for warp and advising you it needed skimming before fitting new studs, gasket etc and reassembling. Bit naughty for you to be having to pay, and pay again beacuse of this oversight.

Any BF mechanics (dandy, smartmoneky, others?) care to chip in?

Good luck getting it worted.

Mike

smartmonkey · Post by **smartmonkey** » Wed Jun 13, 2007 1:33 pm

Yup, you need a new or skimmed mannifold. Most garages won't bother checking.

mikeonb4c · Post by **mikeonb4c** » Wed Jun 13, 2007 2:42 pm

I wasnt going to spit it out, but AVA sould not be excusing themselves using the 'most garages' line as they are Bongo specialists. If a numpty like me (steady now lads!) can work out the warped head thing, they should certainly have considered it. However, we dont know WHAT AVA thought or did, so best not get all funny with them - they may have a v good explanation, assuming of course the problem IS a warped manifold.

Mike

haydn callow · Post by **haydn callow** » Wed Jun 13, 2007 3:17 pm

Is your No 1 manifolld stud still in place ?? It's the only one you can see at the extream left.

RobnKathryn · Post by **RobnKathryn** » Wed Jun 13, 2007 5:03 pm

I would guess that if AVA did the work they have already skimmed the manifold. I had the same problem and ordered a manifold gasket from AVA a while back and the (extremely helpful) guy on the phone told me not to bother replacing the studs and gasket without skimming the head as the stud would just shear again. So they are well aware of the problem.

I I took my manifold to a guy to get it skimmed, and he said that it was so badly warped and twisted that he would replace it if it was his. So, I got a previously owned but very straight manifold from Bellshill for a reasonable price (another very helpful guy). Problem solved.....it's been fine for 10K.........I should say though that I fitted a new cylinder head at the same time after a overheating episode so I know that both mating faces were good.

mikeonb4c · Post by **mikeonb4c** » Wed Jun 13, 2007 11:24 pm

It'll be interesting to see how this one pans out - keep us posted.

neil/di · Post by **neil/di** » Wed Jun 13, 2007 11:51 pm

http://www.igmaynard.co.uk/bongo/forum/ ... highlight=