'87 740 GLE ignition timing

ccb222 · Post by **ccb222** » 23 May 2006, 18:24

Long story short--Timing has been "off" since I bought this car but has been o.k. for around town 'til it recently started stalling. Installed new distributor, rotor and cap (all in rough shape). Installed distributor exactly in the position of the old one and car performed much better BUT, timing was still off (>20 degrees BTDC). I adjusted timing to 12 degrees BTDC as specified and this position is beyond the bolt channels in the distributor. I have vice-gripped it in this position and driven the car--it runs great, but PLEASE TELL ME WHAT TO DO about not being able to put the bolts back in to hold it properly! Thanks for any advice you can send my way. Charles ([email protected]).

Kmaniac in California USA · Post by **Kmaniac in California USA** » 24 May 2006, 00:39

Sounds like the previous owner (or someone hired by them) removed the distributor and reinstalled it "one gear tooth off". I would suggest removing the distributor and reinstalling it correctly.

ccb222 · Post by **ccb222** » 24 May 2006, 11:52

Re: my distributor--Thanks for the idea, KMANIAC, and let me know if it still applies given that the distributor: a) is rear mounted at cam shaft height; b) has a smooth shaft;
c) has only two "cogs" that appear to be the turning mechanism. So, if I remove it and reinstall it, won't it be off 180 degrees? That aside, an acquaintance of mine suggested the timing belt might have been replaced in the past "one tooth off". What's your opinion. Would hate to get into the timing belt unnecessarily and would much rather remove the distributor again!

Kmaniac in California USA · Post by **Kmaniac in California USA** » 24 May 2006, 23:07

Well, I must plead ignorance when it comes to my knowledge of how the distributor mounts in a Volvo 2.3. Yes, I have observed the horizontal position as it sticks out of the back of the head in my 740. I have never been inside the valve cover to see how it attaches. Given what you describe, there should be only two ways to install the distributor, either correctly or 180 degrees out (there is a similar mounting arrangement for the distributors in my big block Chryslers). Given this arrangement, it is quite plausible that your cam is one tooth off at the timing belt. I believe that you can check this with minimal disassembly.

ccb222 · Post by **ccb222** » 25 May 2006, 04:33

I'll check that out today, KMANIAC, (hopefully with minimal disassembly) and I'll let you know what I find. Thanks for all the help to date! Charles

ccb222 · Post by **ccb222** » 25 May 2006, 19:11

I did check the timing belt and it was "off". Interesting, though. The Chilton Manual says to align it at 12:00. In fact, there's a mark on the back of the plastic housing that surrounds the timing belt and that mark is closer to 11:00. The belt I removed was perfect, save the damage I did to it in removing the crank shaft pulley, so it must have been put in by a Chilton Manual owner prior to my purchase. In any case, new belt installed, everything reassembled, and distributor now set properly with the bolts about mid-way in their channels, so all is great. I assume my lousy mileage will improve as a result of all this. Learned tons of stuff--now I think I'll change the timing belt on my '95 850 Turbo wagon. Yes or no---what do you think? I took a look at Volvospeed, I think it was, and the procedure is laid out clearly with photos so I'm confident I can do it. I do know the belt has outlived its expected life and shudder to think of what Volvo would charge. THANKS for your help!! Charles

ccb222 · Post by **ccb222** » 25 May 2006, 19:13

The pulley I was referring to as being "off" and incorrectly instructed in Chilton was the Cam Shaft pulley. Without this info, the above doesn't make a lot of sense, I guess. Charles

Kmaniac in California USA · Post by **Kmaniac in California USA** » 25 May 2006, 22:50

A positive outcome and a happy ending. That's what I like to hear. Thank you for the education about the distributor. I won't be so fearful of it should I have to take mine apart. It is disappointing having to undo someone else's do-do, but at least the fix was simple.

wyoben · Post by **wyoben** » 29 Jul 2019, 07:07

This is an antique thread,but have the ame problem ...my question is do I have to take the cranck acsessry pulley off,or can I just align said accesory pulley on zero, loosen the tensioner and jump the cam pulley to line up at 12 with the cam dot , and what is the timing 12 BTDC or 12 ATDC , and last ...facing the engine left of the zero is BTDC ,and right of the zero is ATDC ? why is the 10 mark what I presume to be ATDC ,if the engine spins clockwise , and it is most likely to be timed at 12BTDC car is 88 B230ft W/hall sensor

wyoben · Post by **wyoben** » 29 Jul 2019, 09:21

Dead Thread Redemption ?