arluk3

When I advance my timing as far as possible, turning the distributor all the way, it seems to yield about 12 degrees of advance. My pulley only has a single notch in it, which I assume is TDC. The three marks that supposedly exist in the area of 16 degrees are not to be found on my pulley ! My pulley is clean. If those marks were painted on, they are gone now. I have calculated that the central mark of those 3 marks (16 degrees) should be located 0.89" from the TDC notch. When I advance my timing as far as possible, I still don't get it to move that far. I think I am getting about 12 degrees maximum advance. Has anybody seen this before ? Could the previous owner have installed the timing belt incorrectly ? The car runs fine and gets nearly 50 mpg, but I would like to set it up properly. Thanks for any input.

cbstd

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by arluk3 &raquo;</TD></TR><TR><TD CLASS="quote"> The car runs fine and gets nearly 50 mpg, but I would like to set it up properly.</TD></TR></TABLE>

If that is not proper operation, what is?

Cam and ignition timing seems to be the number one question about old Hondas. Twisting on the distributor without the benefit of a timing light is NOT a good idea.

If your car is running good, we can assume that the Cam timing is correct. Once the cam belt gets old, it can slip a notch and the engine will run poorly.

Are you looking in the right spot for the timing marks? The TDC mark is a single mark on the crank pulley. The +/- marks for ignition timing will be at about 10 o'clock position as you look ast the pulley from the fenderwell.

As for pefromance, leave the ignition timing alone. The factory set it there for a reason.

If you want a cheap, easy ignition improvement on your old Honda, replace the centrifical advanbce springs in the bottom of the distributor with lighter springs from the hardware store. This is an old Hot Rod trick called "recurving the distributor."

Scott

arluk3

Like you said, the factory set the timing for a good reason. Problem is, there is no way that it is 16 degrees BTDC on my car. With full advance on the distributor, it is about 12 degrees. The pulley is about 6.4 inches in diameter. Doing the math, 16 degrees (factory spec) would be 0.89" away from the TDC notch, instead of the 2/3" that I measure. My pulley doesn't seem to have the +/- marks that are shown in the official workshop manual, so all I can do is measure how far the timing mark is from the TDC notch using a 6" rule. The elongated slot in the distributor is useless in my car because I cannot get all the way to 16 degrees. Perhaps it isn't the proper distributor (I never thought about that possibility). Oh, and I don't know how I gave you the impression that I have been twisting on the distributor without using a timing light. Thanks for your reply. You're the only one to reply to either of my two threads on this issue. My question is still not answered. I'll just drive it the way it is, but I will always wonder if it would perform better with the proper timing.

arluk3

Here's some new information .... I was working in the dark and found the 3 marks on the pulley (both sides) for the first time. I marked them with a white pencil and then used my timing light. I verified that my timing is only about 12 degrees BTDC when the distributor is cranked as far as possible. When the engine was cold and running about 2500 rpm, the advance was beyond the marks, probably about 20 degrees or slightly more. When the engine warmed up and dropped to 750 rpm, the advance was about 12 degrees instead of the spec'd 16 degrees. Could the springs be responsible for this ? Could lighter springs fix the problem ?

cbstd

Now is the time to check your cam timing. It sounds like your timing belt has slipped a tooth. If it has, replace the belt and your water pump (the water pump lives unde the timing belt and so you should replace it while the belt is off).

Scott

gp70hs

Their is another possibility. The timing comes off of a pickup located under the rotor cap, on the distributor. The pickup is mounted on a plate which has 3 screws which hold it onto the distributor. The plate has elongated holes in it. You should be able to remove the distributor cover and look at the plate. It may be that the plate is mounted so that it limits your advance to less than the timing light. Hope this helps.

p.s. I don't know if I'd be fiddling with it, if I was getting 50mpg.

arluk3

Thanks for the input about the distributor plate. I've seen that problem before in a Subaru (it was a lousy design, IMO). I'm happy with my gas mileage, but I have to wonder if it could be better by advancing my timing another 4 degrees.