Timing belt issues

vgames33 · #1 05-11-2009, 01:12 AM

My friend has an '89 Merkur XR4Ti with the 2.3T Ford engine. It has always stalled when getting off the highway, so he usually bump starts it before coming to a stop. Yesterday, however, after the bump it started running like crap and sounded like it was firing on three cylinders. The timing belt was tighter than usual and was moving back and forth on the pulley. We found it to have jumped time and he started changing the timing belt while I did other things.

He installed the belt three times, checked it by turning the motor over with a ratchet, and found the timing to be correct. As soon as he hits the key, it jumps time. It got dark before we got a chance to look for a cause, but if anyone knows where to begin looking, please let me know. I need this car out of my driveway ASAP.

Moppie · #2 05-11-2009, 01:22 AM

Did he replace the tensioner at the same time?

vgames33 · #3 05-11-2009, 01:37 AM

Yes. It spins freely.

Moppie · #4 05-11-2009, 06:24 AM

And was the belt then correctly tensioned?

Airjer_ · #5 05-11-2009, 09:43 AM

Most belt install directions tell you to turn the crank by hand several times to make sure everything is fine with the belt/alignment/tension. You can do this with the timing cover off so you can watch everything while your turning it.

vgames33 · #6 05-11-2009, 10:53 AM

The tensioner is one of those spring-loaded ones that supposedly adjust themselves. The spring assembly did not come with the new tensioner, so it was reused. How can I check for proper tension? I know that the belt is tight and has very little slack.

MagicRat · #7 05-11-2009, 11:02 AM

Those 2.3 liter engines have a spring-loaded tensioner that must be bolted down.

New belts are installed with the spring tensioner arm's bolt loosened slightly, so tension is maintained by the spring itself.

However, that tensioner arm's bolt is tightened up after belt installation, so the arm does not move.

The idea here is to allow the spring to find the correct position for the arm. Then you lock the arm in place with the bolt.

If you leave the arm loose, the tensioner arm and belt will flap loose as soon as you start the engine.

vgames33 · #8 05-11-2009, 11:32 AM

He claims to have tightened that bolt, but maybe it want tight enough? I'll take a look later.

MagicRat · #9 05-11-2009, 11:39 AM

Quote:

Originally Posted by vgames33

He claims to have tightened that bolt, but maybe it want tight enough? I'll take a look later.

Take a look and have your buddy put the engine together, then start the engine with the plastic timing cover off.
Watch the belt and see what happens to the belt and tensioner as soon as he starts it.

vgames33 · #10 05-11-2009, 01:37 PM

I went out and looked at it myself. I did not have the key, so I could only turn it over by jumping the solenoid, but it sounded fine and appears to be staying in time.

He does not have the plastic cover (just the ignition timing part), so he followed someone elses instructions for lining up the cam and distributor sprockets, but if anyone can tell me a quick way to make sure its right, that would be great. He will be over tonight after I get off work, so maybe we can get this thing running.

MagicRat · #11 05-11-2009, 02:09 PM

Quote:

Originally Posted by vgames33

He does not have the plastic cover .

Yuck. The plastic cover has the cam timing marks on it.

When the #1 piston (the front one) is at top dead center (when the valves are closed) the timing mark on the cam sprocket must point at the timing mark on the plastic cover.

Without the cover, you can only give it a good guess. Roughly, the cam timing mark must point to about the 1 or 2 o'clock position at TDC, as I recall.

My '87 Mustang (with the 2.3) was missing the timing mark in the plastic cover. I had about 3 hours of trial-and-error to find the correct timing mark. I would select a set-up, start the car and see how it ran, them disassembled the belt and tried another set-up. I eventually found the correct position, but it was a bitch, through.

vgames33 · #12 05-12-2009, 01:56 AM

http://www.allfordmustangs.com/forum...imingcover.jpg

We are guessing based off of pictures such as that one. The cam is oriented roughly as shown.

I toyed with it some more, confirmed that everything is still lined up, but the engine is still trying to backfire out the intake and will not start. Pulled plugs for cylinders one and two and got only 37ish psi of compression from each (battery is charged). I'm assuming the cam is still out of time. More to come tomorrow.

One thing we noticed was that every time I moved the distributor past a certain point with the ignition in "RUN," the fuel pump would cycle. Shaking the wires that were nearby didn't do anything. Is this normal behavior or should I be looking for a shorted wire as well?

MagicRat · #13 05-12-2009, 07:53 AM

Quote:

Originally Posted by vgames33

http://www.allfordmustangs.com/forum...imingcover.jpg

We are guessing based off of pictures such as that one. The cam is oriented roughly as shown.

Yes, that is correct. I realized in the middle of the night my "1 or 2 o'clock directions were erroneous.

vgames33 · #14 05-12-2009, 01:34 PM

Since I was hearing compression bleeding through the air filter, I tried advancing the cam a little. I got around 55 psi compression from cylinder #1 from doing that. Sprayed a little oil in and saw no change in readings.

I'll try a little more trial and error tonight.

Is there anything else that could have been damaged by the bump start? Someone suggested that it may have broken the distributor drive gear, but I cannot feel any play in the rotor when trying to turn it by hand, and since the distributor is on its own shaft I'm assuming it has nothing to do with the valvetrain or compression. The belt does not appear to be slipping on either gear once the tensioner is locked in place.

vgames33 · #15 05-13-2009, 12:06 PM

Well, he gave up and we pushed it up the road to the shop. I'm afraid that something is majorly wrong with the car, since I've never gotten more than 55 psi out of it (my neighbor has a 2.3l ranger that we checked to confirm that the cam was set within reasonable distance of the correct mark). The 2.3l is supposed to be non-interference, but the car had been modified before he bought it (we know nothing about its history) and is much faster than a stock XR4Ti (never taken it to a track, but we have a friend with one that raced him and lost by several car lengths), so perhaps the head has been milled or someone put a big cam in it. The turbo and fuel system appear to be stock, and the dash gauge says that the boost isn't turned up, but the ignition timing was advanced pretty heavily (around 22*), and he says he has the big VAM upgrade. I hope he didn't trash the valvetrain, but he did have plans to upgrade to a cam and big valve package from Esslinger. We'll see what the shop says. Thanks for the input. I'll let you know what happens.

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