280sl Cranks but won’t start after service

[cjpoulos]

Hey!
After replacing my head gasket and cleaning the cooling channels due to overheating, I’ve gotten my car reassembled. I timed the crank/cam, and the FIP. While she was apart I also cleaned my injection lines, serviced the WRD, serviced the CSV and set point gap and spark plug gaps. I’ve tested all my spark plug leads and leads to the distributor, and they were all around 1.7 ohms - healthy. I bled the air from the fuel filter canister, and also bled the injection lines. The fuel pump works very well and the fuse is not blown. When I tried to start the car, it was trying pretty hard to start. After a few tries it fired up very, very briefly and immediately shut off. It did that a few times. Now when I crank it, all I get is the starter - it makes no effort to start. Any ideas? Thanks!

I’ve also replaced the water pump, thermostat, radiator and various other things, but I figured those are unrelated to a degree.

[Vander]

What is the part number of the head gasket you installed? There are 2 different head gaskets for a M130 engine, and if the wrong one is installed it will not start. You can pull the spark plugs and see if coolant is getting in there, that is a sign the wrong head gasket is on.

[Cees Klumper]

Check also whether your are getting spark, and fuel (are the spark plugs wet with fuel, hopefully not coolant)? Also check compression. If all three check out (fuel, spark and compression) then the only other thing it can be is timing.

[cjpoulos]

Good point. I checked out the numbers for the head gasket and they were correct for the m130.983. I’ll have to run a compression test now. I’m getting spark and fuel luckily. I’m also pretty confident in the correctness of the timing. I’ll keep you all posted, thanks for the tips!

[Vander]

Good point. I checked out the numbers for the head gasket and they were correct for the m130.983. I’ll have to run a compression test now. I’m getting spark and fuel luckily. I’m also pretty confident in the correctness of the timing. I’ll keep you all posted, thanks for the tips!

There are still 2 different head gaskets for a m130.983 head. An early square style, and a later oval style. Compression test is a good place to start.

[cjpoulos]

Oh good to know. I’ll do some more digging. At this point when I crank it, it tries to start, almost sounds like it has some large cams, but it won’t fire up. There’s fuel on the plugs, and no leaks, so I believe I’ve solved all of the fuel issues (for now). I’m going to pick up some new plugs tomorrow, but I’m wondering if the ignition timing is off. I’m not too good at checking that but I bought a timing light so I’ll see what I can do.

[merrill]

distributor 180 degrees off?

[cjpoulos]

I’m guessing it’s ignition timing now. I’ll have to look through the forums and find the procedure for timing it properly but hopefully I can have it done this week - we still have a little time left for a drive before the roads are salted!

[cjpoulos]

Update - she runs! Now I have a new set of problems. There’s a slight exhaust leak from the manifold to the downpipe, which seems like a simple mistake of not tightening the three connecting bolts enough. She runs rough now. There’s also decent amount of vibration and a slight squeak that sounds like it may be from the valve train. Not quite “pinking” but perhaps the timing is slightly off.

My problem before was a simple question of replacing the spark plus which I, against my better judgement, decided not to replace as the car ran decently well with them before this recent round of major service. They were the factory fitted plugs as the car only has 14,800 miles.

[Cees Klumper]

Are your spark plug leads in the correct order?

[cjpoulos]

Yes, that was the first thing I checked when I noticed it was running poorly. I’m wondering if the timings off by one or two teeth. My plan for now is to check the timing chain and go from there. I’ve already timed the distributor and FIP.

There’s also some white smoke from the exhaust. Im hoping this is only because when I pulled the head recently the block did not drain at all except into the cylinders. The cooling channels were so blocked that the block wasn’t able to drain at all, and the car would only take about 2.5 gallons of coolant max. I cleared the coolant from the cylinders immediately and prepared everything for reassembly, and I did a compression test this morning and all cylinders were around 150psi or slightly higher. I’ll let you all know what I find tomorrow!