Camshaft Timing

[TheAlien1980]

I am about to replace my headgasket. While I disasabled my engine, I encountered somthing that I don't unterstand:
I turned the camshaft untill the marks on the camshaft and the journal on top of the camshaft were aligned. As far as my knowledge goes, the zero mark on the flywheel should now align with the mark on the "engine side cover", but they are 6-10 degrees off.
Any ideas? Was my "camshaft timing" way off? If it was, could this have been the reason for my engine to slighly overheat on a regular basis?

[Crazyswede]

I always use the marks on the cam sprockets themselves. Also you need to put the exhaust sprocket on firsr with the chain tight and then the intake

[TheAlien1980]

Did not notice marks on the cams. I'll check the next time I am working on the car.
I did check the intake cam first and then the exhaust cam (with a tight chain). I just used the exhaust cam picture because it was easier to spot the marks in the picture...
The only thing I am not certain of is if the mark on the "engine side cover" is actually a zero timing mark.
And if it is, what the actual side effects would have been with the timing of like this...

[DeLorean]

For one, you should turn the engine by the flywheel or the crank bolt - I use a flat head screw driver on the flywheel to turn the engine. happens slowly, but that's how it should be done.

Also, the crank rotates twice for every single cam rotation. So, actually... if you put the crank / flywheel to 0, you are probably going to be as close as you can get...

Can I see a picture of the cam position when you 0 the flywheel? The cam timing is sometimes a bit... fiddly, especially when the tensioner guides are a bit worn. It can appear like they are a little off from the marks, however when the flywheel is sitting at 0 dead, you want those marks to be pointed as close to the V as you can get em, accounting for the fact that the chain slack will be taken away on the tensioner side once installed.

[SwedeSport]

Is it a new chain, guides and tensioners?

They will stretch a little over time. If you have it apart far enough to change all the chains and guides and such, I would say do so.

It is normal for it to be not perfectly aligned, but that seems a bit far out to me.

maybe one of the sprockets is off by a tooth?

[Crazyswede]

The mark you have in the first photo looks correct....its a little fuzzy in this photo but it looks correct. If you look closely at this photo you can see the two alignment marks ...one on each sprocket...aligned to TDC.



I have never used the marks that you indicated in the pictures of your cams. Be sure the chain tensioner is not installed in the head. Then line up the exhaust sprocket on the marks with the chain tight on the outside of the the sprocket. Get this onto the cam or close and then put the intake on as tight as you can get it with the mark still lining up. Once both are on and the bolts are tight then put the tensioner back in the head and tighten down. Lastly...rotate the intake cam with a wrench slightly in the CCW direction until you here the tensioner click.

[TheAlien1980]

Thank you for all the advice of how to get the timing right.
A couple days ago I finally got my cylinder head back from my machine shop (cleaned, new valve stem seals, all new intake valves, pressure tested, resurfaced) and I was going to install the head on the block. So I checked the block again and after a little cleaning I discovered this :

I am not sure what to do now. It also looks like one piston has lost a piece of metal smaller than the size of a needle head on the outside edge, but I will have to take the piston out of the head to take a closer look.

[TheAlien1980]

So what's the way to go? Get another block that just needs a "rehone", new bearings, probably resufacing and live with the higher compression or get my current block bored out to the next standard size, get new pistons and get all the damm stuff balanced? I don't know how many payed workhours these two aproaches would cost me. I don't know. I am kinda lost here. I just want to do it right this time...

[Crazyswede]

Can't really see what your nlock photo shows. Clean it up well. Is it cracked?

[TheAlien1980]

Two of four cylinders look like the one in the picture. They are quite rough at the silverish, shiny areas. Almost feels like sandpaper when touched. I don't think they are usuable as they are right now...

[TheAlien1980]

This picture is probably better.

[Crazyswede]

Yeah that's weird. Was the engine sitting for a long time? On a healthy engine...even one with 200k miles you should still see the factory cross hatchng on the cyl walls. What is your goal with tjis engine?

[Luke]

That's what happens when an engine sits with water in it for a long time, probably from a blown headgasket, rusts, and then is started and run for a while. Unfortunately that block is toast.

[TheAlien1980]

Well, the engine was runnig rather normaly most of the time and no white smoke came out of the tailpipe. But it startet like s**t sometimes, but only sometimes. So I wasn't too suspicious. It was also leaking every now and then due to brittle hoses in front of the cylinder head, badly designed hose clamps and a broken heater valve, I also had problems because of a broken ignition coil that made trouble in humid weather, so it took me quite a long time to get all this sorted out and to figure out that it probably also had a broken headgasket. One day it wouldn't start anymore, and since I had no money and time for the car back then, I put it in a garage for about a half year. That was probably not a good idea. Oh well, in the end, it turned out it actually wasnt just a broken headgasket, there were to cracks in the cylinder head. And I suspect they were there the hole time.

My goal is to get this engine reliable to stock perormance. As soon as I have achieved this, I want to put T5, a 2,5° exhaust and downpipe and an equal length header on it. More modifications are not allowed by the MOT-inspection guys in my country and I actually don't want more. As I said, I want to keep it reliable. But all this is pie in the sky at the moment. Only T5 is really tempting at the moment, as I have almost all parts for it.

I already overhauled the whole transmission (also put in a quaife differential), suspension and breaks. Now I also have all new hose clamps, water and vacum hoses for the engine. I am done with searching for leaks

So you say, the block is not repairable? Get another block and just put new bearings and rings in? What would you guys do?

[99Super]

The block is repairable, but would need bored w/ new pistons. I've run engines worse than that that have lasted years, but that's not what you want.
I think you are correct that a clean used block, honed, with fresh rings and bearings will do what you need.

Sorry to hear about the extra work

John