Cam timing marks
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RRoller123
- Patron 2020
- Posts: 8179
- Joined: Sun Nov 13, 2011 2:04 pm
- Your car is a: 1980 FI SPIDER 2000
- Location: SAGAMORE BEACH, MA USA
Re: Cam timing marks
just a little more info: if you upgrade a 2L engine to the large valve head, it turns it into an interference engine.
'80 FI Spider 2000
'74 and '79 X1/9 (past)
'75 BMW R75/6
2011 Chevy Malibu (daily driver)
2010 Chevy Silverado 2500HD Ext Cab 4WD/STD BED
2002 Edgewater 175CC 80HP 4-Stroke Yamaha
2003 Jaguar XK8
2003 Jaguar XKR
2021 Jayco 22RB
2019 Bianchi Torino Bicycle
'74 and '79 X1/9 (past)
'75 BMW R75/6
2011 Chevy Malibu (daily driver)
2010 Chevy Silverado 2500HD Ext Cab 4WD/STD BED
2002 Edgewater 175CC 80HP 4-Stroke Yamaha
2003 Jaguar XK8
2003 Jaguar XKR
2021 Jayco 22RB
2019 Bianchi Torino Bicycle
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BigMacDave
- Posts: 50
- Joined: Wed Sep 14, 2016 2:41 pm
- Your car is a: 1978 124 Spider
- Location: San Antonio, Texas
Re: Cam timing marks
Thank you for those tips.
The manual does talk about slacking, but not in that much detail. Thats a big help.
The manual does talk about slacking, but not in that much detail. Thats a big help.
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phaetn
- Patron 2018
- Posts: 575
- Joined: Thu Jan 02, 2014 7:42 pm
- Your car is a: 1974 Fiat Spider 1800
- Location: Ottawa, ON Canada
Re: Cam timing marks
No problem.
I forgot to add, of course, that after turning it over by hand to make sure everything is still lined up. That's when you can tell if something slipped or not.
I had an annoying issue last year when the exhaust cam would always be off by one tooth after I cranked it by hand: everything else was good, but that kept going off. Must have had to do with slack. I kept at it and kept at it, but boy it was frustrating.
More recently I have installed adjustable cam pulleys. The exhaust one slipped in its positioning about a month ago and the engine just lost pull after 4,000 rpm. It was fine up to that point, but then wasn't breathing right and I could feel it wasn't happy. These engines are best between 3,000-5,000 rpm and I could tell it wasn't in its sweet spot. Readjust the synchronization, problem solved.
Cheers,
phaetn
I forgot to add, of course, that after turning it over by hand to make sure everything is still lined up. That's when you can tell if something slipped or not.
I had an annoying issue last year when the exhaust cam would always be off by one tooth after I cranked it by hand: everything else was good, but that kept going off. Must have had to do with slack. I kept at it and kept at it, but boy it was frustrating.
More recently I have installed adjustable cam pulleys. The exhaust one slipped in its positioning about a month ago and the engine just lost pull after 4,000 rpm. It was fine up to that point, but then wasn't breathing right and I could feel it wasn't happy. These engines are best between 3,000-5,000 rpm and I could tell it wasn't in its sweet spot. Readjust the synchronization, problem solved.
Cheers,
phaetn
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BigMacDave
- Posts: 50
- Joined: Wed Sep 14, 2016 2:41 pm
- Your car is a: 1978 124 Spider
- Location: San Antonio, Texas
Re: Cam timing marks
First, thank you all for your help.phaetn wrote:No problem.
I forgot to add, of course, that after turning it over by hand to make sure everything is still lined up. That's when you can tell if something slipped or not.
I had an annoying issue last year when the exhaust cam would always be off by one tooth after I cranked it by hand: everything else was good, but that kept going off. Must have had to do with slack. I kept at it and kept at it, but boy it was frustrating.
More recently I have installed adjustable cam pulleys. The exhaust one slipped in its positioning about a month ago and the engine just lost pull after 4,000 rpm. It was fine up to that point, but then wasn't breathing right and I could feel it wasn't happy. These engines are best between 3,000-5,000 rpm and I could tell it wasn't in its sweet spot. Readjust the synchronization, problem solved.
Cheers,
phaetn
Here it is on. Before i clean everything and button it up, i wanted to make sure this looks right. I don't remember the belt riding on both sides of the aux shaft, but i did turn it 3 full revolutions tdc on the cam marks and everything feels good.
So, is that the way it should be? I don't see any other option, but i just wanted to check.
Thank you as always
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ORFORD2004
- Posts: 1120
- Joined: Wed Mar 17, 2010 9:48 pm
- Your car is a: 1983 PININFARINA
- Location: Sherbrooke, Qc, Canada
Re: Cam timing marks
If your crank mark is on 0 yes you are good.
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phaetn
- Patron 2018
- Posts: 575
- Joined: Thu Jan 02, 2014 7:42 pm
- Your car is a: 1974 Fiat Spider 1800
- Location: Ottawa, ON Canada
Re: Cam timing marks
Confirmed.
I thought it was maybe odd that the belt was on both sides of the aux shaft pulley, too. I went out and just checked mine. Hard to see behind the timing belt cover that I have on, but my belt is like that up against the flange on the passenger side of the pulley, too.
I guess I am so used to looking at it from the driver's side that a front aspect threw me.
All the best when you go to start it!
Cheers,
phaetn
I thought it was maybe odd that the belt was on both sides of the aux shaft pulley, too. I went out and just checked mine. Hard to see behind the timing belt cover that I have on, but my belt is like that up against the flange on the passenger side of the pulley, too.
I guess I am so used to looking at it from the driver's side that a front aspect threw me.
All the best when you go to start it!
Cheers,
phaetn