This is the second time over the years I have replaced the timing belt on my wife's 740 with a B230F non-interference engine. The first time a few years back went smooth as silk. This time I replaced the timing belt and oil seals because of oil leaks. When I started it, it ran rough. I checked the timing belt and sure enough, it was one tooth off.

On the second go around, after reinstalling the timing belt, I turned the engine several times after triple checking the crank, camshaft, and the layshaft. All three pulleys were right on their respective marks. Man, I coasting now!

I put it all back together and now it won't start. The starter spins the motor fine. But it does not sound like it is firing at all. I checked all the fuses and they are OK. I checked the spark in cylinder 1 and it had a strong spark. I smell almost no gas on the plugs though. What am I missing?

Any ideas or advice are greatly appreciated.

If it ran fine before the t-belt change, then I would suspect that the valve or maybe i-shaft timing are off, if the i-shaft runs the distributor on these. Don't know for sure on the dist location ( cam or i-shaft run) on the 85 700 series. Re-check the timing marks, see if the distributor rotor is pointing at #1, #1 cyl at tdc,#1 cyl valves closed, and/or do a compression test.
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Gary Gilliam Sumerduck VA, '94 940 na Regina , '86 240GL

Some people have reported the camm pulley pin breaking when using the camm shaft nut to manually turn over the engine. If you did it that way check that the camm is spinning. The pulley may be slipping.

I read about how fragile the pins were so I used the crank bolt to spin the engine. The cam appears to be turning fine.

Did you disconnect any wiring?

Thanks for responding Alekat. I don't I unplugged anything. I pulled the spark plugs to make it easier to turn the crank when I reset the timing belt. After replacing the plugs to try the engine, it would not crank.

I read thru the FAQ's yesterday. I tested the voltage at the FI leads and got no reading on either wire to ground or across the two with the ignition switch on run. I hear the fuel pump when I try to crank it. I looked for the Radio Suppression/FI Relay on the inner fender well and cannot find it.

My next move is to pull the console and try resoldering the contacts in the FI Relay.

The 85 has no radio suppression relay. The fuel pump relay behind the ashtray is actually a 2 parter. One for the pumps, one for the FI. Checking voltage at the FIs with the key in run won't show anything. Did you have anyone crank it and check voltage at one of the injectors?

Aleecat, I cranked the engine while checking the voltage in the injector leads. I got 12 volts. I then took out the relay. It had three cracked solder joints, so I re-soldered those.

I now have fuel in the cylinder (wet plugs) and a spark when I lay the plug on the exhaust manifold. YET, it won't crank. Darn......

So, did I install the timing belt with the cam completely out of synch? I tested for TDC by having my finger over the number 1 cylinder. I had air forced out and I assumed that it was TDC firing. I guess I'm two rotations off!!

Its kinda hard to see, but. I would recheck timing marks, and where the rotor points. If you look carefully at the distro cap(removed) its labeled per plug. You can guess-ta-mitt if its close to #1 when top dead center. It sounds definitely like a timing issue.

No, I did not know about doing that. I will check it tonight. After working on the thing yesterday, I decided I would start fresh today. thanks

I'm not familiar with earlier 700s so I don't know which Ignition and FI you have, but in any case, the FI ECU must get timing pulses from the Ignition CU before it will pump any fuel. (This is a long-standing safety feature with Bosch FI).

You may possibly hear the pumps briefly when the Key is turned to ON. If so, it's not the normal crank and run operation and does not verify an OK FI system.
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Bruce Young
'93 940-NA (current), 240s (one V8), 140s, 122s, since '63.