Full engine or head only?

[rfisher]

So I've finally been hit by the s6 engine bat.

My 2004 Tam has done 38k but number 5 exhaust valve has no more adjustment.

Dealer says the seats have sunk into the head.

I plan to drive it for a few thousand miles this year and get a rebuild after that as it a gradual deterioration rather than a major failure.

Actually no. 6 had the best compression and leak down.

Do I go for a head rebuild or bite the bullet and get the whole engine rebuilt?

[peteA]

Full rebuild IMHO....especially if you plan to keep it for a long time

[Don1]

Racing Green believe they can get 450bhp out of a 3.6 at 9k rpm.

I don't see a reason to disbelieve them.... Start saving!

(Sorry to hear about the problem though).

[crypto]

rfisher said:

So I've finally been hit by the s6 engine bat.

My 2004 Tam has done 38k but number 5 exhaust valve has no more adjustment.

Dealer says the seats have sunk into the head.

I plan to drive it for a few thousand miles this year and get a rebuild after that as it a gradual deterioration rather than a major failure.

Actually no. 6 had the best compression and leak down.

Do I go for a head rebuild or bite the bullet and get the whole engine rebuilt?

Forget about "gradual deterioration". In my opinion this is a major issue, just recently it happend on my engine. One seat dropped a little to much, causing the shim to flip out of its seat which was flushed into the scav pump. This blocked the pump, broke the chain and f***d the rest of the engine. Take your car asap to one of the big ones as long the car drives. (and throw the cylinder head away !)

[Robertjp]

rfisher said:

So I've finally been hit by the s6 engine bat.

My 2004 Tam has done 38k but number 5 exhaust valve has no more adjustment.

Dealer says the seats have sunk into the head.

I plan to drive it for a few thousand miles this year and get a rebuild after that as it a gradual deterioration rather than a major failure.

Actually no. 6 had the best compression and leak down.

Do I go for a head rebuild or bite the bullet and get the whole engine rebuilt?

Oh dear, feel for you mate, not a nice place to be.

I would get a second opinion from TVR Power on whether to drive it or not - they may be able to talk to wherever has it now and help with your decision. There is a risk, as has been said, that the shim could come loose and go through your engine block, scrapping bearing shells, oil pumps, perhaps even your engine block (it did with me....). They will talk to you about the bottom end too.

I have been led to believe though that post 2003 the quality of the bottom end was better (but then i thought the top end was too!!).

As i said my 2002 tuscan needed bottom end work, piston rings were at the end of their life and the little end bearings were shot. The rods were fine (there is a lot of criticism of 'indian' rods, but the set were well matched and the biggest problem is end cap matching and little end bearings, so i addressed these specifically and left the rods), and Jason at str8 six said he has never seen one 'fail' as a result of the main rod material failing. All of the big end bearings on mine were shot because the shim had been allowed to go through the engine leaving debris all over the place. Because the shim had jammed the oil pump it had scored the block and rather than repair it i went for brand new, stronger block, with better cooling and oil galleries.

If you catch yours before any bottom end damage you may be absolutely fine...but you may still need some oil gallery improvements to bring it up to the latest spec.

Hope you have some money saved

[sidpinup]

I had the Power 4.3 upgrade and I cant reccommended it strongly enough. Fantastic engine. I don't know your location but you are welcome to have a go.

[rfisher]

Thanks.

Really wanted to put this off for a while as I'm in the middle of a work relocation.

They put 13 shims in apparently so I'm not sure how big a risk it is to drive the car.

Suppose I could just store it for a few months.

Maybe someone wants to make me an offer.

Keep thinking it could be time to get a GTR.

[dpd3047]

Don1 said:

Racing Green believe they can get 450bhp out of a 3.6 at 9k rpm.

I don't see a reason to disbelieve them.... Start saving!

(Sorry to hear about the problem though).

And your point is !! Al Mellings original 3.5 made 404 bhp @ 7500 rpm.

[Don1]

Of course it did sweetheart.

[Don1]

dpd3047 said:

And your point is !! Al Mellings original 3.5 made 404 bhp @ 7500 rpm.

My point is obviously beyond your reach, as is the ability to post something constructive for someone who is in need of help.

OP, I'm sorry your thread has turned out like this.

[Buzz Billsberry]

I've got to agree with crypto. 9 out of 10 times you'd get away with it, but you can guarantee that yours will decide to liberate the internals when you least expect it. I've done a few engines in with issues on stages or at circuits to know when to call it a day or think yep its should be ok! Internal combustion engines live a very aggressive life and any weak points tend to get weaned out just when you don't want it to!

Good look with your decision altho' the GTR sounds very attractive


Buzz

[anonymous-user]

The fact that 13 shims were added . Is this relevant, are not all the followers shimmed?

rfisher said:

Thanks.

Really wanted to put this off for a while as I'm in the middle of a work relocation.

They put 13 shims in apparently so I'm not sure how big a risk it is to drive the car.

Suppose I could just store it for a few months.

Maybe someone wants to make me an offer.

Keep thinking it could be time to get a GTR.

[Toady1]

The rest may have been within tolerance.

[TVR_owner]

If you have a run about and can take the Tam of the road till work etc settles then I would suggest that this is the safe way to go - it will allow you to choose between top end and full build.

[Geoff Ashcroft]

cliffords said:

The fact that 13 shims were added . Is this relevant, are not all the followers shimmed?

Unless I'm reading it wrongly, this suggests that 13 out of 24 were replaced (there are 24 valves, each taking a different thickness of shim), either with thicker or thinner shims depending on which way clearances were going. And that could be follower wear and/or valve seat movement. It just suggests there's a lot of movement/wear going on in the top end and I'd be getting a proper opinion - at least to clarify what you do next.

OP - I'm guessing you never asked the workshop what the clearances were before and after the work was carried out? At least you'd have an idea of wear rates. Either way, its a bit of a bummer. A full rebuild is plenty of dough, but with a five year warranty (other schemes are no doubt available), it has got to add value come resale time. And values of good Tams can only go up - they're far too low anyway.

Good luck with it.

[DonkeyApple]

What would be the risk of only replacing the head?

There must have been metal bits washing around from the head wear, would most have been collected or is there a risk of blocking oil ways etc?

[Toady1]

It doensn't mean that 11 were ok, they may have been swapped with other shims that are in tolerance on other valves, but 13 weren't interchangable.

[anonymous-user]

What is within tolerance?
Is there a specific biggest shim available/or within tolerance for any one valve, exhaust or inlet.

Also is there a diagram anywhere on the head showing exhaust and inlets and numbering them ?

Asking as my rocker top will be off this weekend for a look around and a bit of a measure up in there .

Thanks

[rfisher]

OK - here is my genuine opinion on all this.

First thanks for the replies - I appreciate the knowledge and integrity of the vast majority of PH members.

I'm not going to name and shame but I don't think the garage did a good job and I feel this is an indication of the dead as a dodo state of TVR.

I'm a clever chap who's been driving TVRs for nearly 30 years.

I used to do almost all the servicing and repairs needed on my 3000M and 350i.

This included back end UJ replacement and trunnions.

I've not tackled engines but I know how they work.

I don't know what's inside a speed 6 engine but I'm certainly capable of understanding how they work if someone explained it to me.

The attitude of the garage was basically 'engine isn't right, we can find out what the problem is and it's going to cost a lot to look into it for you'.

They were not particularly friendly about it - I think largely because I didn't agree to them taking the engine out to send for a rebuild, over the telephone when they suggested it.

They also made it sound like that was all part of a rebuild and only mentioned that they charge another £1000 to do that when very directly asked.

I suspect they are not doing well and need to grab as much money off TVR customers as they can.

So I emailed a TVR engine rebuilder and got a few vague emails back. Couldn't really get much sense out of him as to exactly how much it would cost to rebuild the engine or even if it needed a full rebuild. Tried to find out if he was including removal and refit of the engine in his price but just got 'yeah it's £4500 plus vat for a rebuild'.

So I'm not impressed at the moment.

Car is not my main drive so she's sat in my garage connected to a battery conditioner.

I'd like owners who have had rebuilds to pm me with their genuine thoughts on the place they went to. I'm not going to give what will probably realistically end up being £6000 or £7000 to some joker or pisshead. I'm looking for a professional who can behave professionally and isn't having a laugh.

If there's a warranty then I need all the details and evidence that he's actually honoured the warranty in the past.

[black11s]

Whilst I understand you not wanting to name and shame them, it would be useful to all Piston Headers to know who you are talking about.
Any clues?
Both from the point of view of who to refer you to next, and who we ought to be avoiding ourselves...
PM me if you prefer...