Final answer to the mysterious 'flaffing" sound.
Discussion
I posted something here a while back about a mysterious "flaffing" sound coming from my Griff when accelerating quickly under load, and I was loosing half a sump full of oil every 100 miles or so! But it's finally been diagnosed, for the help of any other Griff owners who may have the same problem.
I managed to drive the car to my local TVR specialist who took it for a test drive, he commented on the sound straight away, and started on an investigation. It was found that a head gasket was blowing out oil in a few places, hence the flaffing sound, and it was only doing it under load as the oil pressure needed to be up to get it to the top of the engine to blow out, which is why it never leaked when cold, a video was made of the oil spraying out onto the chassis.
So two new head gaskets are needed, and maybe....a skim, I've had better weeks!
I managed to drive the car to my local TVR specialist who took it for a test drive, he commented on the sound straight away, and started on an investigation. It was found that a head gasket was blowing out oil in a few places, hence the flaffing sound, and it was only doing it under load as the oil pressure needed to be up to get it to the top of the engine to blow out, which is why it never leaked when cold, a video was made of the oil spraying out onto the chassis.
So two new head gaskets are needed, and maybe....a skim, I've had better weeks!
Edited by griff59 on Monday 11th March 09:01
Edited by griff59 on Monday 11th March 09:02
Edited by griff59 on Monday 11th March 09:03
Edited by griff59 on Monday 11th March 09:04
I've not heard of a V-8 suffering oil leaks due to head gasket failure. Any idea at which point the oil is coming out ?
Manifold valley gasket leaks are common on these engines along with sump pan leaks.
My one is also making a similar noise, but it's from the ex manifold gaskets.
Having the head gaskets done soon as well, due to water loss.
Manifold valley gasket leaks are common on these engines along with sump pan leaks.
My one is also making a similar noise, but it's from the ex manifold gaskets.
Having the head gaskets done soon as well, due to water loss.
neutral 3 said:
I've not heard of a V-8 suffering oil leaks due to head gasket failure. Any idea at which point the oil is coming out ?
Manifold valley gasket leaks are common on these engines along with sump pan leaks.
My one is also making a similar noise, but it's from the ex manifold gaskets.
Having the head gaskets done soon as well, due to water loss.
I seem to remember the mechanic saying it was leaking out around the oil ways, and I think they are going to replace the valley gasket as well? Manifold valley gasket leaks are common on these engines along with sump pan leaks.
My one is also making a similar noise, but it's from the ex manifold gaskets.
Having the head gaskets done soon as well, due to water loss.
I just hope this is the case, and the source of the noise, I'm sure it is, the noise only occurs under high load, when accelerating hard, if you take the car out on a drive around town you won't hear it, you need a good long straight where you can boot it, I had an exhaust leak before, and it was there all the time.
The top of the engine has to come off to get at the heads, so the valley gasket would be replaced on the rebuild.
They may take the rocker covers off if the inlet manifold is reluctant to come off, so rocker cover gaskets should be replaced too, unless they are very recent because they are not torqued down very hard.
They may take the rocker covers off if the inlet manifold is reluctant to come off, so rocker cover gaskets should be replaced too, unless they are very recent because they are not torqued down very hard.
ianwayne said:
The top of the engine has to come off to get at the heads, so the valley gasket would be replaced on the rebuild.
They may take the rocker covers off if the inlet manifold is reluctant to come off, so rocker cover gaskets should be replaced too, unless they are very recent because they are not torqued down very hard.
Hopefully all that will be done if necessary, I've taken it to Dan Taylor, he's very good, he's called me a couple of times to keep me posted on what needs doing etc, he even made a video of the oil blowing out. I only live a few miles away from his workshop, I should have her back by early next week, hopefully, I'm already getting withdrawal symptoms.They may take the rocker covers off if the inlet manifold is reluctant to come off, so rocker cover gaskets should be replaced too, unless they are very recent because they are not torqued down very hard.
The plot thickens, they've got the engine apart, a few head bolts have stripped threads, that's why the gasket is leaking, I think a kit from TVR Power is being fitted today, good news is that the rest of the engine looks good, like its had a recent rebuild, the engine was rebuilt in 2011, and it's only done a few hundred miles since, so hopefully once the head is sorted out all will be fine.
griffdude said:
Good news you’re getting it sorted but pretty disappointing that it’s failed with stripped threads so recently after a rebuild. Was it done privately or at a TVR specialist?
I need to go through the service history, there's tons of it, two box files. The figures for mileage are a bit confusing. I'll post again and let you all know exactly what the figures are.I'm worried about this thread stripping, could it happen again?
Also, are the bolts long, or short, do they go a long way into the block?
I'm wondering if a rebuild or recon is the best way to go, but....on inspection the engine looked like it had been rebuilt recently and is in very good condition.
Hi all, didn't get round to looking at the service history, it's so boring, and the sun was out! Must do it TODAY! but the sun is still out and the garden is calling 
As for the thread inserts, I'm not involved that really, Dan Taylor has ordered a kit from TVR Power, I trust that he knows what's best to do in this situation.
As for the thread inserts, I'm not involved that really, Dan Taylor has ordered a kit from TVR Power, I trust that he knows what's best to do in this situation.
Just having second thoughts about this rethreading idea for the head bolts, I'm wondering? Questions...Will it happen again and how likely? Would a rebuilt engine be a better answer? Will the fact that inserts have been used affect the value or the desirability of the car in any way whatsoever?
griff59 said:
Just having second thoughts about this rethreading idea for the head bolts, I'm wondering? Questions...Will it happen again and how likely? Would a rebuilt engine be a better answer? Will the fact that inserts have been used affect the value or the desirability of the car in any way whatsoever?
Thread repair in any form (helicoil, timesert, keensert etc) are all quite common and well proven systems so should not be an issue.With respect to resale value...how would the buyer know and why would they need to. This is a normal repair and is in no way a 'bodge' it is a pucker engineering solution.
Steve
The sidewinder carrier pylons on Sea Harriers often had helicoil repairs carried out for the securing of the cowls. Sea air frequently corroded the fittings. Good enough the Royal Navy. Well it was in the 1990s.....
(Not the missiles themselves I hasten to add, only the carrier and its air deflector cowls)
Which loctite variety to hold them in is important.
(Not the missiles themselves I hasten to add, only the carrier and its air deflector cowls)
Which loctite variety to hold them in is important.
Many race engine builders using alloy blocks often fit steel thread inserts anyway initially due to frequent rebuilding thus avoiding problems later on when carrying out routine freshen ups etc , my preference as always been Wurth Time-Serts but they are not cheap and its these I am referring too , used them since the 80's and they just work
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