Damaged cam cap on fresh head

[BlackBox]

Hey all,

Just got the head for my rb25det neo back from being ported and reconditioned..

I have noticed the front intake cap appears to have been damaged in transit.

It is not perfectly round where the seal sits, there is also 2 small cracks, 1 where the seal sits and another on the top surface.

I understand these caps cannot be replaced without getting the head linebored.

Would this cap be OK to reused considering there is no damage to the surface that sits on the cam?

I have emailed the company that reco and ported my head but won't get a response till next week..

If I was to try and recoupe my losses through the transport company it will likely take a long time and I may still be down $$$ to get a new head or get this repaired

[Dobz]

Better off not to dodgy up that damaged cap.

You can find a cap off another head and fit it without necessarily needing a line bore. It needs to be dummied up, measured and checked that the cap sits concentric with the bottom. You would want to get the engine re conditioner to do this because they will have the measuring equipment required. I've done this in the past with success after a cap mysteriously went missing. The heads would be machined with good enough consistency in the factory that a lot of caps could possibly be interchanged between heads.

[BlackBox]

Thanks mate, I'm pretty pissed off at this point just seems to be one thing after another. I will have to wait until Monday to get a response from the machining shop but hoping they had some sort of insurance on the freight.. if a cam cap cannot be sourced is having them line bored a practise that has been done before and would it be a very cost effective repair?

[Dobz]

Not sure on the line bore because i've never had to do it. You'll find out from the workshop once the easier options have been exhausted i guess. Put out a wanted to buy and see if people have got any old heads laying around to pinch their caps. 

Just by chance I may have one floating around in the garage at my mum's house. I'll let you know by Monday.

[KiwiRS4T]

Why are you emailing? Get on the phone.

[BlackBox]

Because many businesses don't answer their phone at 7pm or over the weekend...
I got ahold of him anyway and the plan is to pull the head back off, send it to him and he can fit another cap and ream/bore it

[R_34]

I'm running with an other cap that the one the head came with. Two trackdays and some km on the roads and no signs of wear on the cam nor the cap so you can use another cap if needded.

This cap is not extremely loaded because the timing belt is pulling the cam downward and all the efforts of the springs on the 1st cylinder are handed by the 2nd cam journal. This one is really just the support for the cam seal.

And the fact that these cracks are black inside mean that they are there since a while, you just didn't noticed them before I think.

[BlackBox]

Did you ream or linebore the head, or meaure it when you put the other cap on?
It was definitely not damaged before, it would have been picked up by myself or definitely by the machine shop, and there was another mark on the front of the head where it looks to have been dropped.
Regardless the head is back off and packaged up to be sent away on Monday..

[R_34]

Nope and nope.

I fitted the cap without the cam to "check" the alignement visually but didn't measured it nor linebored it. As it sat flush with the head I just installed the cam and tested it but checked it twice since the installation (after each trackday) and nothing to report, it work as it should.

 

Do you think that the head fell off on the cam cap during transport ? The box where the head came in should show some trace of this shock. Anyway this will take time to get it repaired. Given its position I wouldn't mind using an other cam cap, doing it in the middle of the cam where the cap is taking effort from the spring is another story and may need a linebore. But this one is "replaceable" to me as it is not as critical for the cam function, it's there more for sealing purpose.

[BlackBox]

I understand what your saying about the front cap having no load on it, but its off already and the risk is too great..
I didn't really preserve the box for inspection when I unpacked the head, but I am sure it has been dropped. I got the head back 4 weeks ago but it has been sitting boxed up on the shelf waiting to be installed, If that Is enough time for the cracks to turn black.
There was no insurance on the freight and I expect I will have to cop the full cost of it myself

[Scott Black]

Also worth noting that just because one person as got away with something doesnt mean everyone can, might of just got lucky and found one that worked.

[Scott Black]

Also on that last pic. The deck hight on the block looks about 40mm short. If you have head off you should fix that too. There's a good write up on how to do that in the rb30 area

[BlackBox]

Sorry mate not sure I understand, are you saying it looks like my block is 4cm short? :s
Could you link me to the thread?

[Scott Black]

Just me being a smart ass as the 3l rb30 block is 4cm higher