Help! Car will not start after timing belt replacement

[FiatMac]

I believe the factory cam gear for the '75 was one of those plastic gears with a steel insert hub. If so, the bond between the hub and plastic may have loosened up allowing the hub to rotate with the bolt while the outer portion of the cam wheel was stationary.

[MaineSpider75]

I finally solved my issue after some further investigation online. Despite my best newbie efforts, my intake cam was not aligned properly for TDC. All of the pictures I could find online for the cam timing marks showed a hole as a reference point. My intake cam did not have a hole, so when I originally rotated the engine to find TDC with the old belt on, everything else appeared to be in the correct alignment, and the intake cam had an A pointing to roughly 11 o'clock. My assumption was that the A represented the pointer on my intake cam and I was good to go.
I made 2 mistakes on my first attempt:
1. I didn't search further online for variations in pointers on the cams. If I had, I would have found the pic that I found this week which showed my intake cam and the pointer actually being a solid line from the center of the cam out to the edge.
2. I did not use anything to actually verify TDC in the #1 piston. This second time I used a straw to make sure I was at TDC before re-installing the belt.

So, having discovered my mistake, I removed the new belt and used a socket wrench to rotate the intake cam until it was aligned properly with the timing marks found behind the cams themselves (something else I wasn't aware of on my first attempt). I re-installed the belt, but before I attempted to start the car, I re-adjusted the distributor which I had rotated in my efforts to get the car started previously.

Once the distributor was back to pointing at #4, I held my breath and tried to start the car. Low and behold the car started! It ran pretty rough considering I had rotated the distributor and screwed up timing, but I had a functioning car once again.

I have since adjusted the distributor to the best of my ability to get the car idling smooth and everything seems to be ok. My problem is that I left my timing cover off when I replaced the belt so I could monitor for leaks out of the cams etc, and since I had screwed up the distributor position with my previous efforts, I'm left to use my best judgement. Engine seems to be running ok, so I hope I haven't bent any valves or done any other kind of damage.

If the car continues to run ok, I think I'll leave the timing cover off for the remainder of summer and just enjoy the car before the snow flies. I can drain the radiator and put the cover back on during the winter and get the car properly times at that point.

[RRoller123]

You could do a compression test now to see if you have done any serious valve damage. That will also queue up any further work that may be needed next Winter, and you could start collecting the parts at your leisure now if so. But at any rate, it is a relief to hear that it runs well! And it looks like you may have dodged a bullet. In the absence of timing marks, you can alternatively time the engine with a vacuum gauge to the maximum STEADY vacuum and you will be very close to correct, maybe a little advanced. STEADY is the key word, if not careful it will be too far advanced. This method does work, although there is controversy regarding it. I timed my '79 X1/9 this way for 5 years, over 135,000 trouble free miles.

[ez2wire]

Similar problem:

Dont have cover to check the crank position so set it by rocking the motor and finding TDC with a screwdriver in the plug hole.

Can get it to start but it will idle SLOW.. ( Under 400 ) - should note it sounded like it was firing on all 4.

Try to rev and it spits fuel out the carb and dies.. ( Valve timing to crank off ? )

Tried a second time and before I started it checked the compression

Compression is low 70-0-70-70 the zero bothers me a little, but the numbers are so low and the I did add oil to the pistons before testing so possibly due to being cold and no oil that maybe why #2 is a issue ( as noted when I did get it to run for a few minutes.. it was firing on all 4 .. just really sow ). So for now will worry about that once I can get the car in time.

Ran into a few other issues though.. the bolt that holds the spring tension ( this is a 75 ) broke in the block..



Also.. couldn't find anyplace to get a vacuum for a vacuum gauge on the carb or a place to adjust the idle on it. Ill hit up the forum search on that though.

[nelsonj]

I've broken that same bolt, twice. I now have a normal bolt with a extra nut on it as a make-shift replacement. (The tensioner bearing bolt is now doing the primary job of holding everything in place.) Both times I forgot to loosen the tension bearing and tried to pivot the tensioner "triangle" and that broke the bolt. You'd think I would have learned after the first time.... Neither of my shop manuals mention loosing in the tensionor bearing, go figure.

BTW, you really need to get to the bottom of the "O" compression. If it really is "O" you bent a valve (or two) and will have to pull the head and replace the valve. Not a quick job...

Good luck.