more timing questions

Good morning, this is a question that's probably been asked a million times on here and now a million and one. Just installed a weber carb on my 1990 b-2200, all vacuum lines have been removed execpt the one to the Dist, and the big line from the carb to the charcoal canister. I have checked and rechecked my timing, making sure it's at TDC and Dist pointing @ 9;o,clock. Problem is i can get it running but only if the Dist housing is all the way against the stop going counter clock wise. I took the hold down bolt out and rotated the housing a little further and it didn't improve, so the sweet spot is right at the end of the Dist throw, but it still runs like crap even at this spot, what could be some things i need to try? All vacuum line ports are plugged, adapter plates on carb where sanded flat, ATV ( brown) was used in the sealing process, I'm stumped!!!!

Do you have a timing light? Are your plug wires in the correct order?

First of all, if you didn't pull the distributor or rotate it during the process of installing the Weber, then the timing would not change. My guess is that there's a vacuum leak, and if you try to time the distributor with the vacuum line connected then it will be different every time you set or check it (I know this from experience). Did you check the Weber adapters for ABSOLUTE flatness, or sand them flat using wet/dry on a sheet of glass? And use brown goo Permatex Aviation on the gaskets, and torque them securely and evenly using blue Loctite? That's what we at MazdaTrucking.com would do. Because vacuum leaks at those surfaces are quite common. I even use rubberized sheet gasket on mine, cut my own gaskets, because I had the same issue 4 years ago when I rebuilt my engine, and had issues timing it.

So I'd say fix the vacuum leak first, then worry about the timing. Set timing at like 800 rpm with the vacuum line plugged, the advance wouldn't be kicking in at that rpm anyway. And if you actually removed your distributor, it's also possible that it's "off" a gear tooth, there's multiple ways the thing "can" go back in. So you may need to rotate the engine to TDC #1, the rotor should be at the 9 o'clock position then as you look at it.

Your cam timing is off one tooth. You probably need a timing belt if you didn't take the distributor out recently. The belt stripped one tooth The carb issue is a red herring.

I did the sanding on the adapters, used the brown goo to seal it, that is up until the last gasket that goes under the new carb, didn't want anything getting up in to it. So did everything that i have read from the trucking forum. have every vacuum port plugged except the one for the Dist, unplugged the ECM and still cant get it to run right. Crank and cam pulleys are lined up, Dist is at 9 o;clock and pointing to #1. I changed the timing belt awhile back, before i installed the Weber carb, it lacked power, but ran well. Now it feels defenetly like a timing issue. I have put it forward a tooth and backward a tooth with no luck. Could it be the cap, plugs and plug wires?

I still think you need to reset the distributor placement. It sounds like the distributor needs to be pulled and reset to be at 9 o clock at 6 btdc. From your description you have it lined up at TDC and that would make the spark timing off (late) by six degrees

I think I'm picking up what your throwing down. So set the crank pulley not at TDC but at 6 btdc and then insert the Dist at the 9 o:clock position?

Well not sure if that's what you meant, but tried it and no luck. When i did get it running enough to put a timing light on it, and everything set at TDC and the dist @ #1, the timing mark on the crank pulley was probably about 2" before even getting to the cover timing marks. There has got to be something I'm over looking?

The way I did this set up anytime I had to was to rotate the engine to 6 degrees BTDC on the compression stroke, pull the distributor out of the head and then rotate the gear to make the rotor line up when it was installed in the head. It will rotate a few degrees as it is going into the head and that lines it up at 9 o clock. The fact that you are firing 2 inches to the left of the timing marks is evidence that you have the timing over-advanced.

Here's what I did on mine. OK, first: timing belt has to be correct. Then rotate the engine and use a drinking straw and the mark on the pulley and set to TDC for #1 (each piston has its own TDC). Then install/reinstall the distributor if (1) the rotor does not point to about 9 o'clock as you look at it and (2) the slot in the distributor should show the threaded hole for the bolt in about the middle. Then I timed with timing light. See these two links from a site where I can actually find things: http://www.mazdatrucking.com/B2200//B2200_Timing_Belt.html and http://www.mazdatrucking.com/B2200/B22TimeCheck.html