Thread: 350 '93 Buick Roadmaster Won't Ignite After Changing Head Gaskets

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I would think it is a timing issue, but I made sure it wasn't 180 degrees off, took the rocker covers off twice and turned the engine over three times, watched when the 1st cylinder's rockers didn't move coming up to TDC, loosened and re-tightened the rockers. All wires are connected afaik, and I quadruple checked the spark plug wires, even bought new ones. There is spark, I've seen it, but the spark was red not blue. It seems to be turning over quickly, my dad guessed it wasn't under compression because the rockers were too tight, but I loosened them. What could I be missing? I turn the distributor when it is on KPII and 1 out of 3 times the injectors squirt out some gas, but usually nothing happens. The Engine Coolant Temperature Switch is broken, it's bolted into the block, but as far as I know that only sets off a "Overheating" light, and isn't connected to the ECU. What should I try next?

The TBI caught fire while cranking it over. I put it out quickly.

When you see the intake valve closing bring the timing mark up on t.d.c. and make shure the rotor is pointing to cyl. #1if not pull the dist. up enough to point it to #1 in the dist. cap or if the valve covers are on remove #1 spark plug hold your finger over the hole when and turn eng over till you feel compresson and set timing mark on t.d.c. and then set dist in P/S how did you determin you needed head gaskets

Is your engine an LT1?

Originally Posted by DennyW

Check to make positive that you are not 180° out of time with the cam.
Is the plug wires in the correct firing order ?
Pull No. 1 plug, take a sandwich plastic bag, or similar push it into the plug hole with your pinky finger, then just bump the starter until it pops out. Then turn the crank by hand to bring No. 1 to the top. Now check distributor to make sure it is pointing to No. 1 cylinder. And if you still have the valve cover off, you can also watch the rocker action.
Red spark means weak spark. Check all connections.

Originally Posted by ted dehaan

When you see the intake valve closing bring the timing mark up on t.d.c. and make shure the rotor is pointing to cyl. #1if not pull the dist. up enough to point it to #1 in the dist. cap or if the valve covers are on remove #1 spark plug hold your finger over the hole when and turn eng over till you feel compresson and set timing mark on t.d.c. and then set dist in P/S how did you determin you needed head gaskets

Turns out I had overtightened the rockers so much the valves weren't closing! I didn't have a good understanding of what valve lash was. 5 turns too tight. The car is timed and running like a top now, save for the coolant leak that just popped up.

Originally Posted by DennyW

Well, now you know how to set the valve lash...

((coolant leak that just popped up.))

Did you use sealer on the head bolts ? Did you make sure the intake fit correctly ?

The leak is/was from the drain petcock. I shouldn't have ever removed it to drain the radiator. I hear it's more problem than it's worth. I retightened it by hand, hoping it won't blow out again. Newest problem is the tachometer isn't working anymore. Would you happen to know which connector I most likely didn't attach correctly?

Is this engine an LT1 with an opti-spark distributor???????

I usually take the bottom radiator hose off.

Easier and quicker.

Radiator hose removal won't drain the block

Originally Posted by DennyW

We would need to know what tach you have, and distributor you are using. Standard delco style ? What brand of tach ?

Hmm it should be the standard delco style distributor and tach, the one in the dashboard. The service manual has a diagram of all the electrical connectors in the engine bay so I'm going to go through that.

Originally Posted by jerry clayton

Is this engine an LT1 with an opti-spark distributor???????

Nope LT1's came out in 1994. It's your typical 350.

actually LT1s came out in 1992 but weren't available in all GMs that year

Originally Posted by jerry clayton

actually LT1s came out in 1992 but weren't available in all GMs that year

You're very right. My mistake, I Just know 1994 is the best year for the RMW. It has the LT1 with a towing package and the nicer dash with real gauges.

I forgot to update this post! The tach problem became glaringly obvious when I looked at the wiring diagram. It was because I forgot to reattach the timing connector. You are supposed to unplug it to do the timing and it directly feeds the tach. Surprising, I have no idea what it really is for. The car is working beautifully though!