My woodhauling Sub is down

[captndavie]

No ideas on my problems or thoughts?

 

[LumberjkChamp]

No ideas on my problems or thoughts?

Its a interesing problem. When you mention a potential "intake problem" are you refering to the intake manifold, or its various vacuum lines that connect to it? If there are intake vacuum manifold leaks present then it is more likely that the engine would start and then stop.
If the engine starts good cold, but then won't start hot I would suspect something other than vacuum leaks. An easy one would be the air filter -is it dirty or clogged?. Another, a bad engine ground (this can cause other misterious issues too). The fuel pressure is key also. Fuel might not be reaching the injectors due to clogged fuel tank vent lines. That should get you back on the diagnostic train.

 

[captndavie]

Yes I was referring to the intake manifold. I remember at the forest service we had a mid to late 90's Chevy 2500 w/350 that a intake problem and a Dodge 2500 w/318. I can't remember specifics but I know one of them was using oil bad and it turned out that it was sucking it in and burning it due to a intake manifold problem. I think I am going to see if I can get up with the mechanic out there and see what he thinks.

I here people talk about fuel pressure regulator problems and fuel pump problems. But I just don't know what to think or where to start. I keep thinking about the truck that was sucking oil and wonder if it is possible that something like that could be causing both of my problems(oil use and hard start when warm).

I had Chevy dealership look at it and all they did was check fuel pressure. They couldn't get it to hard start. They wouldn't let it sit long before trying to restart. The guy finally calls me back and says that they finally got it to hard start and it showed slightly low fuel pressure when hard starting occurred. However all the rest of the time fuel pressure was good. That makes me think it is something other than fuel pump. Why would the pressure only be low when the truck is warm?

Oh and Chevy dealership said I need to replace fuel pump for the mild sum of about $500!

 

[captndavie]

I have changed the air filter also. Forgot to mention that.

I want to say thanks for all the help because I don't want to be changing parts to figure out what is the problem or problems.

 

[bejay]

chevy did have some intake problems but mostly with coolant leakage that I know of it wasnt uncommon for the coolant to leak into the crankase and mix with the oil on the small block engines not sure that the big block had that issue.
how much oil does it use in 3000 miles.
im guessing that your fuel pressure regulator is probably bad causing a flooded start issue when warm sometimes, and the oil consumption is probably just a leak or it could be burning some oil due to worn valve guides or seals you said the plugs looked bad if they had deposits built up on them then its burning some oil, did any plugs look alot worse then the others?

 

[LumberjkChamp]

I agree with the above post. The 350 is known for its intake manifold problems. My '95 sub has had 2 in its lifetime (I did one of them). But, I'm not sure if the 454 had the same problem -I don't think it did. If you do have a intake manifold gasket leak then you may also notice some coolant loss. Keep in mind that coolant can evaporate when in contact with a hot engine so in addition to checking the level in your rad. pay attention to the smell of burnt coolant.

As far as your question about why the truck would be only hard to start when warm, the condition is known as vapor lock. As mentioned in my above post this is caused by clogged fuel tank vent lines. Maybe a quick internet search on the problem can help you understand better as I am sure you can read faster than I can type. Let us know.

 

[merlynr]

Try holding the accelerator on the floor when encounter hot start issues. I know it's fuel inj, but still makes a difference

 

[captndavie]

Now that you mention it that was the problem we had with the chevy and the dodge was sucking oil in the intake.

I do not have any oil coolant mixing issues.

All the plugs were nasty, not really much difference between them. I would bet it would be the valve guides or seals then. I can't imagine all the cylinders having that much problems with all the rings. This suburban had 69,000 miles on it last summer so I know it has done some sitting, dried out valve seals maybe? As far as the oil problem goes should I start out with a compression test? If it is in the valves what am I looking at as far as to get that fixed $ wise?

So maybe it is either the vent lines or fuel pressure regulator that is causing the hard start.

I will be glad when it warms up, its too cold to be turning wrenches outside.

 

[super3]

69000 miles on it when you got it. How many 100s of hours just sitting idleing?

 

[LumberjkChamp]

69000 miles on it when you got it. How many 100s of hours just sitting idleing?

Thats also a good point. Being a gov. rig it probably idled a ton.

As far as the valve seals go, is there a greasey mess of built up gunk on the rocker covers? Also, leave it idleing for 10 or so minutes, then have a helper increase the rpm's a little and see if blue smoke comes out of the tailpipe (an indication of burnt oil). Both of these symtoms together often mean some top end trouble.
Valve stem seal replacement insn't a big deal so that is good news. The engine can stay right in. The valve covers come off, cylinders get filled with compressed air so the valves don't fall in, seals get replaced and everything is better than new -or something like that.

 

[captndavie]

Who knows on idle time. Just no way to know without an hour meter. They used it to pull a boat, carry guns to the shooting range and some else. Any way I don't think it was a frequently used vehicle from what I gathered from talking to the guy who was last assigned to it.

 

[LumberjkChamp]

Who knows on idle time. Just no way to know without an hour meter. They used it to pull a boat, carry guns to the shooting range and some else. Any way I don't think it was a frequently used vehicle from what I gathered from talking to the guy who was last assigned to it.

Either way you probably got a good deal on it. For just shy of 70,000 miles, whatever minor problems it has are well worth the trouble in dealing with. Once you get the kinks worked out you'll have a nice truck that will serve you with many more thousands of miles with just a little upkeep.