Worlds longest Resto, my C2 2.7 19/3/18 Vent guage action

[Simon13]

no, why would i? the valves would never hit with it being 180 out

[oguz327]

FFS Si, sorry to hear about this.

As the other homos said, take a little break, come back fresh and hit it again, it will get there!

[B7]

After taking a break I would:

Get the oil light working
Pull the fuel relay and king lead and crank see if there's oil pressure.
Compression test.

The valves shouldnt clash if 180 out on the cam as it's purely on the intake stroke not compression. However, the latter test above will iliminate any possibility for sure.

Si. If you want me to pop over with the compression tester one evening, just shout.

[Jhonno]

Fuck sake Si mate! I know how you feel.. Put it down, and come back to it. Maybe do a few other little 'satisfying' jobs be it car or something else based.

[Demlotcrew]

Si, only losers put things down and come back, at the weekend pull the engine and start diagnosing. There is very little you can do now, just think about how you go about repairing it. Always plan for the worst.

Andrew

[Demlotcrew]

After taking a break I would:

Get the oil light working
Pull the fuel relay and king lead and crank see if there's oil pressure.
Compression test.

The valves shouldnt clash if 180 out on the cam as it's purely on the intake stroke not compression. However, the latter test above will iliminate any possibility for sure.

Si. If you want me to pop over with the compression tester one evening, just shout.

Trev, I can't see how an engine can be 180deg out and not bend the valves. Only the timing can be!

If the crank was at tdc and the cam was 180deg out, the valves would be resting on the pistons!

Crank rotates twice for every rotation of the cam. If the cam was out by 180deg or the crank was out by 180deg then both situations would cause valve to piston contact think about it. The crank would have to be 360deg out for no contact, but then it would be perfectly timed up!

Andrew

[Tay]

are but it's a 6 cyl! if you turn the cam 180 then the fron lobes would be in the same position as the rear ones were, and both 1 and 6 are at top! the valves should never touch when 180 out as the piston will always be either at top or bottom, but if it was say 90deg out then the valves would be opening mid cycle then clash!

[Demlotcrew]

are but it's a 6 cyl! if you turn the cam 180 then the fron lobes would be in the same position as the rear ones were, and both 1 and 6 are at top!

Read back what you just wrote, and then tell me there would be no bent valves by doing this.

If the piston is at the top, the valves have to be closed, if you rotate the cam 180deg, the valves on that cylinder would have to then be........?

90deg on a cam or 180deg on the crank, exactly the same.

Andrew

[fowler]

Simon i really feel for you if you need a hand just shout, even for comedy value i will be there like a shot.
I have been in your postion several times with the turbo touring you think it aint worth it but when i works the hard graft is very satisfying

[Speedtouch]

Moral of story: if engine's making odd noises, investigate before driving it any distance.

Are the piston crowns sitting proud of the block, as this photo seems to suggest, or is that OK with the headgasket in situ?

[Eddie25]

Interesting you mentioned the cam noise Si.

Head wise i did similar to you; new rocker shafts,rockers, retainers eccentrics, stem oil seals, cat cam, the works and mine too sounds like a dying M40.

I was going to look into ceramic coating the 6 branch and x pipe this summer to see if that helps.

[B7]

I think andrews right come to think of it. As the dowls were opposite to one another then the lobes would be pointing down instead of up.

However, why did it feel strong in power and the compression test read ok (after it had been spun over). Plus this would have been turned over on the stand by hand with the plugs out and any resistance would have been felt?

[Demlotcrew]

Trev,

At TDC with cyl 1 piston at the top, cyl 1 cam lobes should be pointing down! (Rocker on the cam base circle).

Same with cyl 6 (just a little more retarded).

In my first post, when i said timing, i was referring to ignition timing not crank > cam timing.

Andrew

[gooner1]

However, why did it feel strong in power and the compression test read ok (after it had been spun over). Plus this would have been turned over on the stand by hand with the plugs out and any resistance would have been felt?

While I know SFA about the workings of an Engine, surely
what Trev states is correct and any resistance/interference
would have been obvious. Doesn't this all point to Oil
starvation.

[B7]

Trev,

At TDC with cyl 1 piston at the top, cyl 1 cam lobes should be pointing down! (Rocker on the cam base circle).

Same with cyl 6 (just a little more retarded).

In my first post, when i said timing, i was referring to ignition timing not crank > cam timing.

Andrew

Andrew. I understand. My post matters not if they should be up or down timing wise. I was just stating that when they should physically be up, they'd be down.

Compression test it. I would.

[Demlotcrew]

I think that the bottom vibration dampener was the initial problem, since the compression test simon has moved something 180º and i guess it would be the crank! Thats 90º on the cam and thats what bent the valves.

Its impossible to diagnose from the comfort of my lovely office.

Andrew

[bss325i]

The crank rotates twice for every one turn of the cam.

One crank rotation at 360 deg is 180 on the cam.

On the first 360 deg rotation of the crank the inlet valves open and close.

On the second 360 deg rotation of the crank the exhaust valves open and close.

If the cam is 180 deg out the the exhaust valve will open before the inlets hence the non start.

This is the mistake Simon made and the rectified hence no bent no bent valves and it turning over ok before and after he rectified it.

[Kos]

but why's does it sound like bag of nails from the top ends?

pistons meeting valves

[Demlotcrew]

If the cam is 180 deg out the the exhaust valve will open before the inlets hence the non start.

Dude this is so wrong! Think about it, its not possible! For the exhaust valve to open first the engine needs to rotate backwards!

For one complete combustion cycle, the crank rotates four times and the cam only twice!

Andrew

[bss325i]

If the cam is 180 deg out the the exhaust valve will open before the inlets hence the non start.

Dude this is so wrong! Think about it, its not possible! For the exhaust valve to open first the engine needs to rotate backwards!

For one complete combustion cycle, the crank rotates four times and the cam only twice!

Andrew

No, one complete combustion cycle the crank turns twice and the cam once.

4 stroke engine, suck squeez bang blow.

Think about it.

[Demlotcrew]

so it does!

So if the cam was 180º out and running on the exhaust stroke first, Simon could have simply changed the ignition leads over from 1 - 5 - 3 - 6 - 2 - 4 to 4 - 2 - 6 - 3 - 5 - 1 (i think) and it would have ran!

If the Crank was at TDC and Simon rotated the cam clockwise after it had been 180º advanced it would have most certainly pushed the valves on to the pistons.

Andrew

[bss325i]

He didn't rotate the cam though to correct it. I think he rotated the crank, he will confirm.

[Demlotcrew]

He rotated the crank by 180º?

Andrew

[e301988325i]

the car didn't let you down, you did!

Karma for your response to my problem, perhaps.

I hope it's not terminal for the 'pina, I can't see you shelling (no pun intended) out for another bottom end.

[penton08]

Are the piston crowns sitting proud of the block, as this photo seems to suggest, or is that OK with the headgasket in situ?

I'm no engine builder, but the last m20 i nailed together the pistons where proud like that coupled to a lumpy cam and the valves hit the pistons not enough to stop it turning over by hand but when it fired up it sounded like a diesel!! I pulled it apart again and had the pistons relived a little and it has been fine since. I did not run this engine for any amount of time, so do a compression test first. Gutted for you BTW

[gooner1]

the car didn't let you down, you did!

Karma for your response to my problem, perhaps.

I hope it's not terminal for the 'pina, I can't see you shelling (no pun intended) out for another bottom end.

Harsh, mate, harsh.

[Simon13]

Are the piston crowns sitting proud of the block, as this photo seems to suggest, or is that OK with the headgasket in situ?

I'm no engine builder, but the last m20 i nailed together the pistons where proud like that coupled to a lumpy cam and the valves hit the pistons not enough to stop it turning over by hand but when it fired up it sounded like a diesel!! I pulled it apart again and had the pistons relived a little and it has been fine since. I did not run this engine for any amount of time, so do a compression test first. Gutted for you BTW

Can i just say the spec on this engine is IDENTICAL to the one in my C2 touring, now thats done nearly 30,000 since i rebuilt that. Makes the power and no valve piston issues either. I checked that when i built it with some plasticine remember people? loads of clearance was over 2mm iirc. You can skim loads of M20 heads especially if they're a stock engine and not worry about oversize gaskets, valve/pistons clash etc

I was going to say what demlot has in theory i could of swapped the ignition leads round and it should of gone.

i'll get the car home this weekend and i might take a look but i'm not too bothered tbh at the moment. I'd leave it at the in laws but they live in middle class heaven and it sticks out0 a touch!

[Simon13]

He didn't rotate the cam though to correct it. I think he rotated the crank, he will confirm.

i didn't rotate anything i'll explain how i did it later with some pictures

[Demlotcrew]

Coolio dude!

[B7]

He rotated the crank by 180º?

Andrew

I would have put it to tdc and then slipped the cam belt off. Then rotated the engine backwards so that all 6 slugs are out the way. Whip the cam sprocket off and relocate it to the opposite dowl and then rotate the cam back to it's timing mark (180 degrees). Then bring the crank back to it's markings and refit the belt.

We'll await the photos. Spoke to Simon earlier and this is a weird one! I suspected one of the new liners may have slipped and carnage but the machine shop left a lip at the bottom of the pot and slid them in from the top so they physically cannot slip down.

[e30topless]

so it does!

So if the cam was 180º out and running on the exhaust stroke first, Simon could have simply changed the ignition leads over from 1 - 5 - 3 - 6 - 2 - 4 to 4 - 2 - 6 - 3 - 5 - 1 (i think) and it would have ran!

no chance,
the cam was 180 out, I had a look at a head today that has a spiky cam in it and with the lobes up top on No1 the valves are slightly open, this coupled with No1 piston being TDC they must have made some contact while the head was being torqued down

I think there's some valve meets piston action here esp with the rockers working loose

[Andyboy]

As long as it hasn't dropped a valve head, a head off job with some new valves should sort it. I'd also replace the rockers on any cylinder where the valves and pistons have touched which might be all of them. Pray it hasn't damaged the head or piston(s).

What a pisser.

[Simon13]

it hasn't dropped or bent a valve! think about it guys. Cam timing 180 out doesn't mean bent valves it just means the ignition timing is out thats all. Thats why it still had good compression! Well i'll be fucked if there is some valve piston action.

[capri_rob]

Fookin hell Si I hope I don't have this sh1t when I put the head back on mine

[Simon13]

you won't Rob