Problems Starting after Head Gasket

[82vdub]

Does your IP sprocket have the two holes in it where you can lock it to the IP bracket, or only the one locking hole? If you didn't line up the notch on the back of the IP sprocket, then it's 180 degrees out of time. Have you verified this also?

[avocado]

Does your IP sprocket have the two holes in it where you can lock it to the IP bracket, or only the one locking hole? If you didn't line up the notch on the back of the IP sprocket, then it's 180 degrees out of time. Have you verified this also?

Two holes, and I believe I used the right one based on the fact it's got marks on it (from when I initially locked it doing the timing belt) as compared to the second hole, which shows no sign of use.

When I put the timing belt back on initially, the locking tool was at a slight angle (on the retarded side) instead of going straight in. Having moved the belt one tooth, it's now at slight angle on the advanced side, but still lines up. I'm guessing it moved while doing the belt and it was "close but no cigar" - i.e. off by one tooth.

Regardless, I don't think I'm 180degrees out. (Although if it doesn't start after advancing it farther, I'll revisit).

[82vdub]

Just double check that the line on the back of the IP sprocket is visible when everything is at TDC. That will tell you if you have the correct IP locking hole or not. I always mark my old belt and sprockets with little dabs of paint and transition paint marks to the new belt and line the paint dabs up. It adds a little time to the project, but if there's ever a 1/2 tooth discrepancy, I know which one it goes on.

[avocado]

Just double check that the line on the back of the IP sprocket is visible when everything is at TDC.

The line on the back of the IP sprocket? I'll have to look for it.

I used to do paint (or nail polish) too, but lately I've been using a sharpie, which isn't nearly as effective. Need to get back to the paint...

[bscutt]

I think the MK2 pumps had the line on the front so if this is a later pump it could be on the front. I seem to recall that the pump on my 92 Eco motor had the line on the front of the sprocket. Either way that needs to be really close to the line on the pump when at TDC, certainly within a tooth.

[82vdub]

Well, if the pump sprocket has a line on it and two locking pin holes, either that line will be visible when the IP sprocket is locked, or it will be under the pump and not visible. If you set TDC at the cam, then this line on the IP sprocket should be pretty close to the position to insert the IP locking pin.

[Fatmobile]

Turn the max fuel screw in.

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Wait, let's back up a bit.....

You said you had low compression and then changed the head gasket.

Did you do a compression test after the new head gasket?

A bad head gasket usually shows up in one or two cylinders, not all four.

Did you put new rings in when you had the head off?

I would verify compression before messing with timing, or you could be wasting a lot of time.

Also, Ive sometimes used a quick shot of starting fluid to get an air-locked engine going.

[82vdub]

Don't use starting fluid unless you disconnect the glow plug circuit.

[avocado]

Wait, let's back up a bit.....

You said you had low compression and then changed the head gasket.

Did you do a compression test after the new head gasket?

A bad head gasket usually shows up in one or two cylinders, not all four.

Did you put new rings in when you had the head off?

I would verify compression before messing with timing, or you could be wasting a lot of time.

Also, Ive sometimes used a quick shot of starting fluid to get an air-locked engine going.

I don't have bad compression, but marginal compression: 350 or above in all cylinders, all about the same except for one at 390.

I replaced the head gasket because I started to have pressure buildup in the coolant system when the temp went over 200degF (which it hadn't done before).

No new rings or otherwise.

[avocado]

Got the engine started, got it up to operating temp, then retorqued the head and reassembled.

Re-started it tonight, but it's still not starting easily or running well: needed the block heater and lots of turning it over to get it started, followed by lots of white smoke once it was running.

I tried to advance the timing by one tooth on the injection pump (as it was already advanced as far as it could go, bumping up against the injector lines) but it's still running poorly: after it warms up, it idles but has lots of smoke and stalled on a trip around the block.

May turn in the smoke screw to experiment, but getting to the end of my tether...

[bscutt]

still sounds like retarded timing or fuel starvation (air in lines?)
Wish I had any spare time I would come over and help.

[Quantum-man]

Too advanced could take injection out of high compression area, resulting in your symptoms. Be inventive try 0.8mm or lower... What are your injectors set to ?

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I don't have bad compression, but marginal compression: 350 or above in all cylinders, all about the same except for one at 390.

I replaced the head gasket because I started to have pressure buildup in the coolant system when the temp went over 200degF (which it hadn't done before).

No new rings or otherwise.

Oh, ok. your original post said 300 psi on all cylinders, which is pretty low. I just wanted to start from the beginning and rule out something that hadn't been addressed.
I agree now that it is a likely fuel timing issue...If the only thing you changed was the head gasket, and the pump never moved, I would not go messing with the fuel screw.
If it was running ok before, and all you changed was the head gasket, then I would think you put the belt back on one tooth off. Even with the pump locked, there is still enough movement to do this. Also, you could have moved the crankshaft when putting the belt back on, its easy to do.
Its not the fuel screw, dont go introducing new variables until you get it running the way it was before. You can end up chasing your tail if you change too many things at once.

One trick I got in the habit of doing before removing a timing belt is to put a drop of paint across the face of a pulley tooth and corresponding belt tooth on all 3 pulleys, with the flywheel notch exactly at tdc. Then all the marks have to line up exactly on reassembly.

[avocado]

Thanks for the replies, Volks.

Did some more digging, watching, and musing. Taking a closer look at everything, it looks as though I've got some fuel leakage at the injectors - just a tiny bit, but easily enough to introduce air into the system. I'm going to make sure my injectors are torqued to spec, the connecting lines (which are new) are all seated properly, etc., and see if that doesn't sort things out. Once I've gone through all of that I'll report back. In addition, I'll be leaving the smoke screw alone for now.