turn the cranshaft without timing belt

[PHILDUFOUR]

Hello

for Turbo SE

a garage have moved out the camshaft few months ago without take marks

In june i have refurbished my engine with new oil pump and shell bearings and my engine d'on't restart

I have checked all the things , electric connection etc

Now I think that the camshaft are at the opposite side of the original TDC

can I move the position without the belt and to turn the crankshaft of 360

[910Esprit]

Seems unlikely. However its very easy to check. If the camshaft dots are aligned, what position is number 1 piston when observed from spark plug hole? (should be top).

[andydclements]

Now I think that the camshaft are at the opposite side of the original TDC

Do you mean you think the crank is one rotation out relative to the cam shafts?

If so, it doesn't matter. The piston of no 1 will still be at TDC, and the valves will either be set ready to suck in fuel and air or keep closed for the piston to be pushed down by the explosion, either way it doesn't matter as the system works on a wasted spark so it will spark at either fuel and air compressed or waste gasses having just been expelled.

Andy

[DanR]

If you want to move the crank without the timing belt first take the plugs out so there is no chance of air compression snapping the crank over while you're turning it. There is still the chance you could hit and bend some valves. If the plugs are left in that air compression could give enough force to do damage.

As you have the belt off turn the crank so the pistons will all be about half way down. The crank timing mark will need to be about 90 degrees further on. You may need to go backwards if you feel some resistance (valves touching piston). If so manually turn the cams and try again.

Now set the cams so the alignment marks are where they should be for #1 piston.

Turn the crank so the marks are lined up. You now have #1 firing.

Refit the cam belt and double check everything is correct. When you're satisfied it is finally put the plugs back in.

If the marks are all correct Andy's right and the problem's elsewhere.

Good luck.

Further edit:

Something else, have you checked the plug leads are correctly fitted to the plugs and coils?

Edited August 2, 2008 by DanR

[PHILDUFOUR]

YES I have checked the plugs

but i have also change inlet and exhaust pulley for 104 MOP pulleys so i m a little lost with the right position of the camshaft and crankshaft

I have put the two pulley* with the yellow dot in accordance bettween them ( *FROM SJ SPORTS)

the crankshaft is on TDC position

the piston is of the top

One more question if i don't start like this can i change the coils of the ignition bloc

for instance change 1 BY 2 AND 3 BY 4

Because the 1 and 4 have the same position and 2 and 3 ALSO

thanks

[DanR]

Could try that and if wrong shouldn't do any harm.

Your cam marks should be:

[PHILDUFOUR]

i have refurbished my engine and i have also add new 104 MOP pulleys for inlet and and exhaust camshaft

thes pulleys have been bought from SJ SPORTS with a yellow dot

my engine don' t start

do you have explanation or it's not the problem of the new position of the pulleys

but an other problem

thanks for your answer

phil

[PHILDUFOUR]

Thanks you

one more question the cylinder 1 is the cylinder rear panel side or opposite

phil

[PHILDUFOUR]

please confirm me

the position of cyl 1 is rear side of front side

thanks

phil

[esprits4de]

It must be something else. If the pulleys were adjusted the wrong way, still the engine would start and would eventually hit the valves with the piston in that case....

Spark?

Fuel?

ECU / sensors /cabeling ?

[DanR]

#1 next to pulleys (Cam fan water etc) #4 next to flywheel.

[PHILDUFOUR]

thanks you

but it's the opposite for my engine on TDC it's the 4 cyl on the top

due to a last camsshaft operation of a garage

and the garage have change the position of ignition

the problem now i m lost

i have change the pulley for 104 MOP and assembly with the dot but i can imagine that the engine don't start due to wrong position of the cames and valves

Phil

[Bibs]

You should really be taking your car back to the garage for them to fix, that's what you're paying them for!

[andydclements]

Bibs gave a very good suggestion, however if they aren't going to sort it for you try the following.

Assuming you have turned the engine over without any noticeable valve to piston issues. Move the engine round to crank indicated TDC.

Remove both cam covers. note a cylinder with the inlet valves open, or turn the engine in the normal rotation to achieve that.

Now slowly rotate the engine by hand (spanner on the crank pulley bolt should be good) and the start of each valve pair opening note the details (eg inlet no3 opening).

You should end up with it being obvious if the engine has the valves opening in the right order (which would only be wrong if the cam pulleys are wrong).

I've assumed you've checked for spark.

Andy

[giorgio67]

Hi Phil,

Have you bought from SJ original Lotus pulleys?

You said 104 MOP yellow dot, but the 104 pulleys are marked only with Green dot, yellow dot is for the 102.5 MOP. (E cams)

Cheers

[PHILDUFOUR]

I HAVE ASKED 104 MOP PULLEYS

AND I HAVE RECEIVE PULLEYS FROM SJ WITH WITH YELLOW DOT !

SO THE AFTERNOON I CHANGE THE PULLEY TO PUT THE STOCK AND I WOULD BE SURE

THAT EVERY IS OK FROM TDC AND PULLEY

MAY BE THE ENGINE DON't START DUE TO WRONG PULLEY

PHIL

[PHILDUFOUR]

thanks you everybody

IN fact GIORGIO ( ghe67) have found for me

it s' not the right pulleys

I have reput the old one ( the stock ) and my engine start normally

PS / Just one remark

IT S possible to turn the crankshaft without the belt like said DAN R

THANKS YOU AGAIN

PHIL

[giorgio67]

[lotus4s]

PS / Just one remark

IT S possible to turn the crankshaft without the belt like said DAN R

PHIL

Just in case someone reads this later and misunderstands, the crankshaft should never be rotated more than 90 degrees from Top Dead Center without the cam belt on. Any more than that and you risk damage to pistons and valves.

[PHILDUFOUR]

Just for your understanding and to avoid wrong information

yesterday I have put the 104mop pulleys and my engine turns very well

In fact I spent long time to understand that the pulleys of SJ SPORTS were OK

my error was a wrong position of inlet pulley

for the inlet pulley it 's necesseray to turn it

and the position is rafly the same of the red dot stock pulley

104

[lotus4s]

OTHER thing I CONFIRM

IT'S POSSIBLE TO TURN THE CRANKSHAFT OF 1 TOUR (360

[andydclements]

There is no reason to turn the crank through one turn.

On a GM system car the system works on wasted spark so fires irrespective of whether it's at the point to fire, or one crank turn out.

On a dissy car the dissy can simply be removed by 6mm, turned through 180 degrees and re-inserted to achieve a spark at the right crank rotation.

Andy