Help with timing on 124 1.6

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Homegrown
Posts: 19
Joined: Mon Nov 27, 2017 1:43 pm
Your car is a: 1971 Fiat Spider 1600

Help with timing on 124 1.6

Postby Homegrown » Wed Dec 20, 2017 8:33 am

Hi guys:
I am new to the board and working on rehab of my father's 1971 that he bought new in 1971. It's been sitting for ~30 years, but ran when it was stored.
Based on advice, I havent tried to start it because of the old timing belt. While preparing to install the new belt I noticed the engine will not rotate fully without making contact internally. Also, the timing is off; see pics.
Image. https://imgur.com/a/wFtJB I'm looking for advice on how to correct.

Can I remove/cut the belt and just see if I can get the aux pulley to line up while keeping cams stationary?
Would the valves have to be damaged if it were only a "little" off?

I am hoping not to pull the head...it may be getting outside my expertise.
Thanks,
Kevin (Mpls MN)

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chrisg
Posts: 746
Joined: Sun Jun 04, 2006 7:30 am
Your car is a: 1971 FIAT

Re: Help with timing on 124 1.6

Postby chrisg » Wed Dec 20, 2017 9:45 am

this may be a situation where you could make use of one of the rather cheap endoscopes that are available to investigate. You should be able to look at the marks on the timing belt wheels to see if things are lined up. you can rotate the aux shaft independently and with any common sense, you won't do damage doing so by hand. That all said, a new head gasket is probably going to be needed sooner than later after it's hibernation, so maybe it's simpler to do it & do the full assessment at the time?
Chris Granju
Knoxville, TN
'71 FIAT 124BS (pretty), '72 FIAT 124BC,'76 FIAT 128 Wagon(ratbeast), '85 Bertone X 1/9, '70 124BC (project), 79 X1/9 (hot rod in rehab), '73 124BS (2L, mean), '74 124 Special TC, '73 124CS, '73 124 Familiare

Nut124
Posts: 748
Joined: Wed Oct 25, 2017 6:39 pm
Your car is a: 1978 124 Spider 1800

Re: Help with timing on 124 1.6

Postby Nut124 » Wed Dec 20, 2017 5:25 pm

Homegrown wrote:Hi guys:
I am new to the board and working on rehab of my father's 1971 that he bought new in 1971. It's been sitting for ~30 years, but ran when it was stored.
Based on advice, I havent tried to start it because of the old timing belt. While preparing to install the new belt I noticed the engine will not rotate fully without making contact internally. Also, the timing is off; see pics.
Image. https://imgur.com/a/wFtJB I'm looking for advice on how to correct.

Can I remove/cut the belt and just see if I can get the aux pulley to line up while keeping cams stationary?
Would the valves have to be damaged if it were only a "little" off?

I am hoping not to pull the head...it may be getting outside my expertise.
Thanks,
Kevin (Mpls MN)


If the car ran when it was stored, then it could not have been off timing wise too bad. IIRC, the crank can hit the gas pump lobe on the aux shaft is the aux shaft is not timed correctly. This would break the crank and/or the aux shaft. The cams need to be timed correctly vs the crank.

Do you have the instructions of how to install a new belt in correct timing? It can be a bit tricky, playing with the tensioner, but you will se when it is correct.

Your crank seems out of time too. In my car, the crank timing marks are on the yellow belt cover. If you cannot rotate the crank to line it up with marks, because of interference, then cut the belt and align each shaft by hand carefully.

Trying to rotate the crank in the wrong direction can make the belt skip teeth. Never do that.

Good luck.

Nut124

Homegrown
Posts: 19
Joined: Mon Nov 27, 2017 1:43 pm
Your car is a: 1971 Fiat Spider 1600

Re: Help with timing on 124 1.6

Postby Homegrown » Wed Dec 20, 2017 10:26 pm

Thanks for confirming that it is possible to try to align without the belt. That is where I may be headed. Hopefully, nothing is damaged because I stopped when meeting obvious resistance. Pic of cam and aux: Image. I'll need to replace cover to check approx location of the crank.

I've been reading a lot about the belt job on the Fiat engine. However, when I felt resistance I did reverse the wrench on the 38mm crank bolt to see if it would rotate in reverse - but ran into interference in reverse too. The belt is very tight so it surprised me to learn that the belt could 'skip teeth'.

I have experience with the 2.7T Audi DOHC timing and cam chains, but then I had lot of tools that lock everything in position including the crank itself.

I ordered a cheap scope to see whether I can make out bent valves or contact on the piston surfaces. I'll post back this weekend with results.

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chrisg
Posts: 746
Joined: Sun Jun 04, 2006 7:30 am
Your car is a: 1971 FIAT

Re: Help with timing on 124 1.6

Postby chrisg » Thu Dec 21, 2017 10:41 am

from my recollection (which, i suppose for thankfully may be "off" since I don't deal with these issue every day), it looks like the aux cam is off...but that's taking the photo & extrapolating about 30 degrees of crank rotation. Seems like I usually have the aux cam about "1 o'clock" and it rotates slightly clockwise as the tension is set...and then, a few rotations by hand to make sure everything is good before trying to start it.

ran when parked is one of those terms I take with a grain of salt. I've had too many cases where i heard/was told/etc. that and found myself wondering how in the hell it ran! Anyway, you're on the right path & it's likely there's nothing needed other than a few maintenance parts and some time. Might also recommend the forum at mirafiori for solid tech help with the TC. have fun!
Chris Granju
Knoxville, TN
'71 FIAT 124BS (pretty), '72 FIAT 124BC,'76 FIAT 128 Wagon(ratbeast), '85 Bertone X 1/9, '70 124BC (project), 79 X1/9 (hot rod in rehab), '73 124BS (2L, mean), '74 124 Special TC, '73 124CS, '73 124 Familiare

Nut124
Posts: 748
Joined: Wed Oct 25, 2017 6:39 pm
Your car is a: 1978 124 Spider 1800

Re: Help with timing on 124 1.6

Postby Nut124 » Thu Dec 21, 2017 12:55 pm

OP, I would just remove the belt, turn each shaft by hand. Rtry to install the new belt with correct timing.

Then i would see if it cranks, squirt some oil in each cylinder via the plug hole and do a crank compression test.

You can buy a crank comp tester - not that expensive nowadays. Normal crank compression would be something above 125 psig. If you see anything like this, then the valves are OK. If bent, you'll zero or under 20psig anyway.

Nut124

Homegrown
Posts: 19
Joined: Mon Nov 27, 2017 1:43 pm
Your car is a: 1971 Fiat Spider 1600

Re: Help with timing on 124 1.6

Postby Homegrown » Thu Dec 21, 2017 6:58 pm

Thanks for continued advice. I put about 10ml of mystery oil into each plug hole the day I pushed the car into the garage and let it sit a day, moved a little, let it sit, moved a little. That worked to help getting the old mustang started anyway.

I did purchase a compression tester and will try that out too. I'll figure out how to use it and post back. The endoscope arrived today so I'll also get that up and running to see what's going on inside.

I've got the new belt, but will need a new tension roller, the current one is...rusty (as evidenced in the photos).

Thanks all!
Kev

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azruss
Posts: 3659
Joined: Sun May 30, 2010 12:24 pm
Your car is a: 80 Fiat 2000 FI

Re: Help with timing on 124 1.6

Postby azruss » Wed Dec 27, 2017 8:22 pm

If the car ran before being parked, I would be reluctant to remove the belt until the car is at TDC. without the belt cover, I can't tell whether the crank is at TDC. If the cam sprockets shifted a tooth or two, the car will run like shit but won't lock up. The aux shaft has a lot of room in the non interference area. 12:45 to 2:30 is all non interference. I usually set mine in the 1 to 2 o'clock position. I've rotated the engine in reverse. just need to rotate from the crank rather than a cam sprocket. pull the plugs so compression won't fight you. If the aux cam is the problem, you should be able to rotate the motor nearly a full revolution before hitting it again. There is always the issue of the rings rusting to the cylinder wall making it difficult to rotate. Squirting some penetrating oil down the sparkplug hole will definitely help get the rings loosened up.

mamsterla
Posts: 69
Joined: Sun Nov 26, 2017 10:10 pm
Your car is a: 1969 Fiat 124 Spider AS

Re: Help with timing on 124 1.6

Postby mamsterla » Wed Dec 27, 2017 10:02 pm

Both the crank and the aux shaft look to be off. I would do as others have said and remove the belt and manually turn the shafts. My car was in a similar situation (about 17 years since it ran). I replaced the belt and set the timing based on a dowel in the 4 the cylinder. To turn the crank, I bought a 34mm socket and put it on a breaker bar. I was able to gently get it moving and after that it has been easy since. I suspect the rings are stuck with some surface rust. Just be gentle when you first get it moving. I would highly recommend hand cranking before trying the belt and firing it up.
I got a cheap endoscope too and it was helpful to see that my pistons and cylinders were in good shape before firing up.
1969 Fiat 124 Spider AS0012768


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