timing new motor woes NEED HELP

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dennday67

dennday67

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Ok for the past couple weeks ive been working on my neighbors 1987 W150 that has the stock dissy and computer on the drivers fender that adv timing. I installed his rebuilt 318 that has magnum heads, I think 10:1 compression, and once again I think mp .484 lift purple shaft cam. we got it all primed and started. I tried to time it but couldnt see the timing mark. (and I did make sure #1 TDC mark lined up and rotor pointing to #1 plug like I always do). adjusted the timing by ear and broke in the cam at 2000 rpm for 20 mins. sounded good, didnt over temp and had great oil pressure. after the 20 mins I lowered the idle and checked the timinging and it looked like it was 25-30 ATDC. Tried adjusting but the closer i got to zero it would die. I pulled the dissy, rotated the gear and reinstalled the dissy after double checking #1 TDC. fired it up again and it was at 15 deg BTDC and sounded good. got it down to 10 deg BTDC and would stumble. back up to 15 deg BTDC in gear it will die. Called the engine builder and he said he used a deg wheel to install the cam. before I redid the timing and it looked like it was at 25 deg ATDC it would at least stay running in gear. and with out touching anything it will step up the idle once in a while. I think there is something up with that computer and dissy. Ive only ever worked with the old school ecu and hei mod. Oh and after break in while we were working on the timing his radiator blew and he had it checked out by a shop.
 
Sounds to me like the timing mark is NOT CORRECT

Buy or build yourself a piston stop like this:

pic_installation.jpg


First time you use it you may have to play with the length.

Remove the no1 plug, make sure the piston is "down a ways" and disconnect the battery ground

Install the device, and wrench the engine around until it stops on the device. Make a temporary mark under zero (TDC) of the timing tab, onto the balancer

Now wrench the engine around counter clockwise, and do the same thing.

You will now have two marks some distance apart. True TDC will be 1/2 way between the two

What are you using for a distributor? It's not, I dearly hope, a "lean burn" distributor? Those have no advance mechanism.
 
I had built one of them a little while ago but not sure what i did with it. I think it is a lean burn system as it doest have the vac adv on the dissy. the vac pot is on the computer. (I told him while I was putting the motor in "Throw that **** away!")
 
dennday67 said:
Ok for the past couple weeks ive been working on my neighbors 1987 W150 that has the stock dissy and computer on the drivers fender that adv timing. I installed his rebuilt 318 that has magnum heads, I think 10:1 compression, and once again I think mp .484 lift purple shaft cam. we got it all primed and started. I tried to time it but couldnt see the timing mark. (and I did make sure #1 TDC mark lined up and rotor pointing to #1 plug like I always do). adjusted the timing by ear and broke in the cam at 2000 rpm for 20 mins. sounded good, didnt over temp and had great oil pressure. after the 20 mins I lowered the idle and checked the timinging and it looked like it was 25-30 ATDC. Tried adjusting but the closer i got to zero it would die. I pulled the dissy, rotated the gear and reinstalled the dissy after double checking #1 TDC. fired it up again and it was at 15 deg BTDC and sounded good. got it down to 10 deg BTDC and would stumble. back up to 15 deg BTDC in gear it will die. Called the engine builder and he said he used a deg wheel to install the cam. before I redid the timing and it looked like it was at 25 deg ATDC it would at least stay running in gear. and with out touching anything it will step up the idle once in a while. I think there is something up with that computer and dissy. Ive only ever worked with the old school ecu and hei mod. Oh and after break in while we were working on the timing his radiator blew and he had it checked out by a shop.
Click to expand...

alot of cam shaft for a 318....it is going to want alot of initial advance...like the 15 degrees you tried...
 
'S what I was thinking FOR A HEAVY TRUCK, and if it really is a 10:1 compression, that's also a lot for a heavy vehicle.
 
That's what you get when the owner doesn't do his research and then has a cheby guy build it. I look at every part and as a whole. People ask me all the time at work how about this build? Then I ask what's it going in, what's it going to be used for and what tranny? Then i get that look like what difference does that make... Ugh... Okay you don't want a double pumper carb on an automatic, dual plains build more torque, single plains build more HP, and too much comp and you will be buying your gas at the air port. Then i get the response but this is how they built it in yada yada magazine. (Guess all my research bs and i don't know ****). Sorry I'm venting and getting off topic.
 
I am running 32 btdc in my 340, with points (yeah, but they always get ya home), but 67273 is correct, you need to make sure the damper hasn't spun out (rendering the stock marks useless)I can see the top of my pistons at TDC, but they are not stock. And throw the lean burn crap away.
 
I can see the top of the pistons as well and I use a straw to watch for tdc off the top of the piston but a stop would be accurate.
 
Agreed, but when I say I can see them ,I mean they are right there (I can read the P/N) Used clay to check piston to head clearance, it was very close, but w/ the permatorque, I was good. (not to get off subject)...
 
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