OK, so the trip to the lakes. Well it was exciting and emotional.
Tim (impmad2000) came with me along with his gearbox. Mike checked that out first - needs new bearing apparently.
Then onto my engine
I was taking it up to try and sort out an oil leak. I say leak, but it was more of a gush really.
When Zentrum built my engine it had a leak from day 1. They said this was because of damage to the case that they had tried to fix but failed. They had the engine back and added in gaskets to try and solve the problem. I'm pretty sure gaskets weren't there before. It reduced it initially but then it got worse again. Over the last couple of years it's got worse still to the point where people don't want to follow me on DDK trips as their windscreen gets covered in oil (I thought I was driving fast as there was always a gap behind me
)
I'd assumed this was because one of the gaskets had failed and the larger resulting gap left a bigger leak. As I stripped it down though there was oil all over the engine. So I was taking it up to Mike to try and find out (and hopefully sort) the reason for the leak.
This is where we ended up
We got part way through, and Mike asked me to decide whether we leave it there or go for a full strip-down for peace of mind. With what we'd discovered by that stage I had to go for the strip-down as there was no telling what had been done inside the case
Interesting things that came out of it
- The cam carriers on cylinders 1,2,3 had masses of rubber gunk put in as a sealant - Tim was pulling plugs of the stuff out. This part hadn't been opened since Zentrum put it together
- I found the damage Zentrum had spotted ( and tried to fix) - looks like someone prior to Zentrum had tried to lever off the barrel with a screwdriver. Luckily I've since bought another case so I'm checking that out today. We'll either use my 'new' one or get the existing one machined and add spaces to restore the compression ratio
- we found this at the bottom of the engine
No not the key - that's there for size. It was chewed up lumps of aluminium. We went all over the case and the internals looking for damage - we eventually found another chunk trapped under the left hand timing chain cog. As it is soft it had moulded itself into shape and luckily wasn't causing further damage. We (Mike) worked out that it had gone in from that part of the engine - i.e. Under the timing chain cover - been smashed about by the harder metals in there and eventually gone through to the main part of the engine where it sat at the bottom. Thankfully it doesn't seem to have caused any damage.
Zentrum were the last people who had the timing chain covers off when they fitted new chain tensioners a few years ago. I can only assume something made of aluminium was used to help fit the tensioners and this was inadvertently left in the patient when it was "sewn up". Many of the chunks were stuck to the mesh on the end of the oil pump feed - thank god/Porsche that was there.
- loctite 541had been used to put the case together and it seemed to have set like steel in certain places, but not sealed the case very well in others
- the valve guides are fine
- a few of the piston rings are worn and need replacing
- chain ramps well worn and need replacing
- the crank is OK
And the source of the oil leak(s)?
Hard to tell specifically, but from the clean and dirty areas Mike thought that one or more of the main bolts had failed - some of the O rings looked poor as they came out. Also the original damaged case was still to blame but to a lesser extent.
So now I'm checking out the other case. The cams and rockers are being sent away to be reground/refaced. Mike is ordering replacement parts that are needed. Mikes also going to take a bit off the heads to increase the compression ratio slightly, and also machine a bit off the back of the valves to improve airflow.
Mike has very kindly agreed to let me help put it back together under his supervision, which I am really excited about. Mike as ever justifies his reputation as the sage of the lakes - Tim and I were talking about it on the way home - it's not just that he knows every nut and bolt and part, and how it should be fitted in a certain way - he knows why it should be fitted in that way, and the consequences of not fitting it in that way. I'm so glad I took the engine up to him
So it was emotional and a bit of an extreme way to sort the oil leaks. However I am really really excited about the thought of driving an oil-tight engine that has been assembled correctly, and that hopefully runs even better.
