Bad day with cam install... think I found the reason.... FIXED & RUNNING.

[Jim 2]

The presoaking thing was clearly a majorly bad idea - but I was sure I'd read it on this very forum. It's looking like (with the absence of any other logical explanation) that it may have played the major role in this problem.

[Jim Bowen 1]

I presoaked mine, done cams 2 or 3 times, i doubt that could cause it to jam up enough to snap a cam. Were you holding the cams down in place while tightening them or almost using the caps as leverage to tighten them. As Kev says i would of expected a thread to strip first or it being incredibly hard to tighten the nuts.

 

Was top chain in place and sprockets on the cams? I can't think of reasons what may have happened, just trying to think it out in my head. I feel gutted for you. How come you were removing the schimmels?

[Kevin Bacon 5]

I don't think soaking the tappets was the cause tbh. They're filled with pressurised oil when the engine runs, so not something that would happen when sat in a tub of oil.

 

It's certainly and odd one for sure, and even odder that it happened twice!

[Jim 2]

We originally tried to install the OE cams and they didn't yet have the sprockets on. The instructions I believe are you install the cams first, then fit sprockets which is what we were working to.

 

In terms of removing the schimmels, just fancied going back to and trying out OE in a bit of a question to put my VR back to pretty much bone stock :) Plus selling them was going to pay for the work I was doing (tappets, injectors, and associated gaskets / bolts, etc) - as it is, technically the job has cost me twice as much now with them breaking :(

[Kevin Bacon 5]

Yeah shouldn't have tried to fix what wasn't broken :D

 

And having gone from Schimmel back to stock, I regretted it immediately. Just felt flatter everywhere in the rev range, especially pulling away from rest.

[Yandards 0]

I don't think soaking the tappets was the cause tbh. They're filled with pressurised oil when the engine runs, so not something that would happen when sat in a tub of oil.

 

It's certainly and odd one for sure, and even odder that it happened twice!

 

They are but at the same time its circulating oil and the NRV in the oil gallery up to the cylinder head will be open not closed allowing that oil to move around.

 

Problem is that the engine didn't move between chain disconnection, it was at the No.1 TDC point and the problem didn't happen when the old camshaft came out - as camshaft installation is the reverse of removal in terms of bearing cap removal the same stress load that caused the camshaft to snap should have existed when the outer bearing caps were removed, it didn't.

 

Couple that with the only change in the entire system being the hyd tappets and it really points to them being the problem.

[Kevin Bacon 5]

Looks like it. Aftermarket tappets have always been a gamble in the VR. Some quiet, some not, and now this!

[Jim 2]

These are INA's... I deliberately didnt buy cheap ones! :)

[Dox 23]

These are INA's... I deliberately didnt buy cheap ones! :)

 

Have you compared old and new tappets for physical size?

[Jim 2]

Yep - they are the same from a visual inspection. Could do with comparing the inner element though (height from the base of the tappet, to the bit that actually rests on the top of the valve).

[Jim Bowen 1]

Are the lifters still fitted? Just wondering if there are any signs of something catching or digging in when the cam snapped.

 

Not sure if it would make any difference but did you have spark plugs in?

[Jim 2]

Spark plugs were removed mate. I've not had much enthusiasm to go and stick my head under the bonnet again yet but I will hopefully this weekend.. will have to go inspect the left most tappets on the exhaust as that's where the problems seem to lie.

[Jim Bowen 1]

I fitted two lots of ina lifters now. I've also kept all my old lifters. Factory and used ina ones. So will dig them out and get pics etc if it helps work anything out. I remember they ina ones are slightly different looking on the underside.

[Jim 2]

Not sure what make the ones I removed are.. will have to grab a photo of the logo on them to see if they look familiar to anyone.

[bruny 0]

Hi Jim, Sorry for late reply, have been away. The INA followers were inspected before fitting, I think they are identical(some time ago now though]. But comparing them some seemed more solid than others. Difficult to explain but when compressed by hand i.e. finger and thumb, some seemed to give others didn't. So tried gently in the vice. Again some gave easily, oil eased out of the little hole. Others gave with moderate pressure, but two of the new ones took so much leverage in the vice I thought they were going to break!! However they did give but with such a crack on release of pressure I feel they would have caused a problem had they not been relieved. Hope this helps, good luck, can't imagine what else could have caused the problem unless the camshafts had been knocked while in storage which may have weakened them perhaps. I may have some spare shafts if thats any help. I will check when I get back if you like. Let me know Jim.

[Jim 2]

Thanks Dave - much appreciated. I've got a new exhaust cam on it's way to me in the post so I should be OK for now... unless I break another one! :|

[bruny 0]

It can't happen again surely!!

[Jim 2]

You'd hope. I might have some external help on this soon so will update accordingly.

[Jim 2]

Well Dave - I think your suggestion of a 'stiff' tappet might be right on the money. I've just gone out to the garage to have another look. The cam we'd attempted to tighten down was the exhaust cam and had broken on the cap which sits between cylinders 1 & 3, suggesting that there was too much resistance from one of the tappets on cylinder one.

 

I popped them both out. The right hand one was nice and springy and easy to push in and out. However the left hand one was rock solid. Pushing it in place in top of the valve there was absolutely no movement. I pulled it out and put it into a G-clamp, I had to twist using some ridiculous amount of force before it began to move, and then was nice and springy like the other one. Putting it back in place I could now push down on it in place.

 

I think we may well have found the culprit. Wish I'd known about checking the tappets prior to fitting them!!

 

I guess once the lower inlet manifold comes back from media blasting next week I think I can move and get it put back together..

[bruny 0]

Hope thats the answer Jim.

I may be repeating what has already been said, and not pretending to be much of a mechanic myself… have you considered that there are two TDC on the pistons, Exhaust and Combustion. Engine would be 180degrees out. Just double check before refitting.

[mic_VR 3]

hope this is the answer mate, and it all goes back together smoothly now.

[robrado974 1]

Best of luck , i hope all goes well Jim .

[Jim 2]

Hope thats the answer Jim.

I may be repeating what has already been said, and not pretending to be much of a mechanic myself… have you considered that there are two TDC on the pistons, Exhaust and Combustion. Engine would be 180degrees out. Just double check before refitting.

 

We double checked timing mate and are pretty sure the engine was at TDC - we checked for the alignment with the arrow on the clutch plate? Will be checking that prior to reinstalling it all though.

[Jim 2]

Got a follow up question actually.

 

Knowing the engine is as stripped down as it currently is (upper & lower inlet manifold off, cams out) am I naive in thinking it's not much more of a stretch to have the head off the car?

 

Reason I ask is we found that the head gasket has actually split just in the area under the cover plate, towards the rear underneath where the tensioner bolt is. I've been advised this isn't really a problem in the same way as it would be if it were actually in the bit where the cylinder head is tightened down and that when the end plate is resealed it should be fine. But it's gnawing away at me a bit and I'm wondering if it's pretty much just a case of removing the exhaust manifold bolts and head studs and swapping over the head gasket to get that replaced?

 

Obviously I'd need to buy new head bolts and the head gasket too...

[g0ldf1ng3r 15]

Got a follow up question actually.

 

Knowing the engine is as stripped down as it currently is (upper & lower inlet manifold off, cams out) am I naive in thinking it's not much more of a stretch to have the head off the car?

 

Reason I ask is we found that the head gasket has actually split just in the area under the cover plate, towards the rear underneath where the tensioner bolt is. I've been advised this isn't really a problem in the same way as it would be if it were actually in the bit where the cylinder head is tightened down and that when the end plate is resealed it should be fine. But it's gnawing away at me a bit and I'm wondering if it's pretty much just a case of removing the exhaust manifold bolts and head studs and swapping over the head gasket to get that replaced?

 

Obviously I'd need to buy new head bolts and the head gasket too...

 

sounds kinda sensible Jim

 

& I am sure it would probably only play on your mind if you choose not to renew the gasket

 

however, once the head is off will it not be too tempting to have the valve seals renewed - seeing as the head is off I'd say it would be worth refurbing that too

 

sorry I know it would be a case of in for a penny in for a pound lol

 

plus that is how I ended up spending so much on my head refurb as it kept being a case of 'oh well it is apart & being refreshed, lets not put old parts back on & get new ones'