18:1 Hard Start

[BiggR]

I've been fighting a hard starting condition on my brothers 18:1 motor. This only happens when the block heater is NOT plugged in, when the block heater is plugged up, it starts perfect! I don't know for sure if the timing is right. I checked it with my Tech 1A, but since it is a '98 OBD II I'm not sure it's telling the truth! Here's a list of what we've done so far:
2 NEW BATTERIES
RJ'S GLOW CONTROLLER MOD
CHECKED POWER TO GLOW PLUGS
ADJUSTED TIMING PER GM SPECS
KENNEDY QUICK HEATS(installed when engine was put in last fall)
The only I haven't checked is if any of the glow plugs are bad...that's next!! Any help would be appreciated!!!! Ronniejoe???

Bigg R

[ronniejoe]

Need to check each of the plugs to make sure all are working. Also, need to check timing with a Tech II. I don't have one, so can't help there. If I remember right, this truck is near by? If so, I'd be glad to stop by and have a look.

If the glow mod doesn't fix the problem, you've probably got one or more plugs that are not glowing. I haven't plugged my truck in since before Christmas. It starts great with new starter and glow mod.

[BiggR]

Yes this truck is close(Green Township). I'm going to check all the glow plugs and make sure every one of them is working. I checked voltage to the plugs and all are getting power,with stock glow circuit and with modified circuit, so I know that much! I can call up all the info with my Tech 1A and do a time set and TDC offset, but the timing is reading somewhere in the 12* to 14* range except in time set mode, where It'll read numbers closer to what I want (3.5*) Is this normal?

[ronniejoe]

What is the TDC offset value? With my TDC Offset at -1.94, I see about 8.9 deg BTDC timing at idle. At 3500 rpm under loaded acceleration, I see 18.8 deg BTDC.

You might want to approach it from the TDC Offset approach, get the number you want there and see what the timing is then. I still think you're gonna need a Tech II.

[BiggR]

I had TDC set at -1.5 initially and timing was around 8 or 9 deg. and engine was pretty noisy, so I set it back to -.6 and timing value went up to 12 or so. This thing reads different than my 95! My truck reads just like yours does, that is if you increase TDC Offset you get a higher actual timing value (8.9), but this one seems to be backwards! I think your right about needing a Tech II!!

BIGG R