Engine struggles under load at idle

[n33k0]

Hello,

My truck has an issue where the engine struggles when an accessory is loading the engine down. Sometimes the A/C Compressor will kill the engine if it engages shortly after starting the truck, whether the engine is cold or hot. If the compressor engages while at a stoplight the engine will drop RPM pretty low, it seems that the idle kick-up solenoid isn't strong enough to bump the throttle on its own and I have to rev the engine a bit to get the throttle lever off the solenoid so it can extend fully and hold the higher RPMs.

Other times, my power steering pump will groan while turning at low speed or while stopped, the steering feels heavy and sluggish, and the engine gets bogged down and dies. The steering issue happens most often when I'm trying to squeeze into a parking space, I haven't noticed any problems while making normal turns on the road.

The truck has a small block 350, Holley 650, TH350. These issues don't make the truck undriveable, they are just random occurrences that annoy me, otherwise she runs strong. Is this normal?

*edit: I have 275/60/15s on all four wheels, maybe the front tires being that wide is what is contributing to my steering problem?

[Jurassic-1]

Could be a few things. Check easy things first. Timing should be approx. 10 degrees and idle should be around 700 RPM you may have a dwell problem if you run points. Check for vacuum leaks . If all is well it should run well at even low RPMs.

[geezer#99]

First thing that comes to mind is your timing set up.
What's your initial timing?

[n33k0]

I'm not sure what the timing on the engine is like. I have been meaning to check it for a while, but I have never checked engine timing before so I have been putting it off, and I don't own a timing light. I can rent a light from my local auto-parts this weekend, that will give me time to learn how to check and adjust engine timing too

[n33k0]

I checked the timing, which measured 24* with the truck in park idling. I don't think the distributor has a vacuum advance, I couldn't spot any vacuum hoses around it.

[geezer#99]

If you got 24 degrees then you likely do have vac advance.
You need to plug it to check timing.
Burn us off a pic so we can see your carb and distributor.

[n33k0]

I can only find three vacuum connections around the distributor. One is a large hose connecting the brake booster to the intake manifold, the other is a vacuum line running from the TH350 to a port at the front of the carb, and last is the PCV valve connecting to the back of the carb.

[geezer#99]

You're right!!
No vac pot.
How well does it start when hot?

[n33k0]

When it's hot, the starter lags a bit when trying to start, I had always thought that was a heat-soak issue since the truck has headers and not the stock exhaust manifolds.

[geezer#99]

24 initial will do that, but I don't suspect your timing reading is correct.
Have you confirmed your timing tab/balancer mark are correct?
What's your idle rpm? In gear? And in park?

[n33k0]

I can't say for sure what RPM the truck idles at, it doesn't have a tach (it's been on my wishlist for a while!)
The tab and balancer mark seem to be correct, but I don't know enough about that to say for sure. I have a metal tab with a few V-shaped notches, and the balancer has a line cut in to it that I think marks TDC. I filled the line with whiteout to see it easily, and used a variable timing light to get the line to fall into the largest V-shape on the metal tab. That is how I got the 24* measurement.


I didnt know that the timing would be able to affect the hot-start issue I've been having. The issue popped up after replacing the carb.

I really appreciate the help!

[geezer#99]

Here's some info on proving your timing tab.
http://www.crankshaftcoalition.com/w...op_dead_center

I suspect your reading because the motor should be extremely hard to start and would be pinging badly with 24 initial.

[n33k0]

Thanks for the advice, Geezer#99. Would the cam in the engine make a difference when determining whether the timing is advanced too far? According to the previous owner, the truck has an aggressive cam.

Either way, I'll try to confirm TDC on the balancer.

[geezer#99]

A wicked cam does effect your timing. Usually way more initial is needed.