SOLVED:Running on 5 cylinders and timing belt issue

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SOLVED:Running on 5 cylinders and timing belt issue

Postby Ronsoft » Mon Mar 13, 2017 7:59 pm

Mivec 2.0 dohc fto.
we have some issues to solve after we did an repair on the half moon seals, because of oil leakage's.

Have change out this "strange type of gasking" half moon seals downunder the topheads.
Checked and changed out all bad "old" oil seals on camshafts and so an.
Replaced timing belt for new and placed it on every right corresponding timing marks on cam and crank.
Replaced all tappets shoes, some were gone, others were hard bross and snapped in two while squeesing...
Adjusted all valves on the right clearances and everything build nicely with bond and new gaskets..
Build everything together, started the engine and runs on 6 steady and nicely.

Couple days later started the engine and knocks out..
We took the cam caps off and dicovered that the front camshaft was off timing 15 tooth (clockwise jumped)
All the other positions on the markings still ok....
We had a bad feeling that front row valves have met the pistons and damage could be have happened.
We performed a compression test and all cylinders looks ok because we have 6 times 11,5-12 barg max.

So whats the reason of the timing belt hops over the tooth?
-The tensioner is not a tensioner but morely a damper to compremise small changes in tension..
-We did have put the timing belt on and we tensioned it with the tensioner, that was wrong :shock:

With this learning curve in mind we put the timing belt again on the timing marks, pre tensioned it, and now spot on.
Turned the crank a couple of times and the timing checks looks ok now..
Build everything together, start the engine and still goes from 6 to 5 and to 4 and stalls within a 30 seconds..

Changed the timing belt timing with the statement in the manual one tooth counterclockwise, maybe that helps..
A quick calc shows that ignition timing could be 15 gr before tdc..
Start the engine, and backfired a couple of times ( occurs when ignition timing is way to early)

Changed the timing belt timing a 1/2 tooth back on the crank :shock: , that means we have to go change position 1
tooth on the camsshafts, so that if all cams are on the proper timing marks the crank position is half a tooth away from the tdc mark. That also means that the ignition is appr. 7 gr before tdc, looks good right?
Start the engine and looks ok, but the same condition still there, start on 6, goes to 5, 4 and stalls...

Sparkplugs are new, leads are new, sparkplugs on the rear are all black and wet (fuel), on front also not so good..
Changed sparkplugs with others, still the same..

We suspect the coil(s)now, can it be possible that the sparkplug underneath is not firing while the slave to the rear does, we have test the plug on the leads, they all firing :shock:

I could not find it, but the timing mark on the crankshaft Pulley tells you were you are in relation with the marks on the coverplate, so 0 gr on it corresponds with the marks on the crank and the sprocket on the block?

We still have an engine running not smooth, we don' t exactly know what to check further..
Also important to mension, there are no faults on the ECU..eventually occured during/after starting the engine a couple of times..

We hope we can have some answers to solve this, many thanks.. :nwor


Ron
Last edited by Ronsoft on Tue Aug 01, 2017 8:34 pm, edited 1 time in total.
Ronsoft
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Re: Running on 5 cylinders and timing belt issue

Postby Ronsoft » Wed Mar 15, 2017 12:33 pm

Yesterday we found out that the MAP sensor is not responding properly, which means that on ambient pressure the ECU is told that more fuel needs to be injected.
If the MAP sensor was working properly the signal to the ECU should be much less demand of fuel...
It could be credible that this issue is bothering us, we go out for a new sensor...

Disconnecting this sensor and read OBD gives fault 32.when starting the engine it run for 2 seconds
When on and reset OBD gives no faults..

Thx, Ron
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Re: Running on 5 cylinders and timing belt issue

Postby Ronsoft » Tue Jul 25, 2017 8:12 pm

We have found the problem and solved it immidiatly.
Thanks for the support :ll
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Re: Running on 5 cylinders and timing belt issue

Postby Kace » Sun Jul 30, 2017 3:17 pm

So what was the problem and how did you fix it?
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Re: Running on 5 cylinders and timing belt issue

Postby Ronsoft » Tue Aug 01, 2017 6:55 pm

Well, i did not ever experienced this kind of weird
mechanical design.
How far do we need to go?
We checked the camshafts and especially the front intake, and found out
that the cam timing was incorrect, while the camshaft timing mark
was spot on..
We took out this camshaft, take off the sprocket and then
(we knew it must be that :shock: )found a sheared off pin, so this shaft was definitely
out of sync...
Change out the camshaft, adjusted again the valve clearances, put everything
together, and started the engine... and yes...running smooth on six and placed my beer
on the stable running engine, that was fun...

So lessons learned, dont take cambelt timing just for granted, look further :lol:
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