Cant get my engine to run. Please help!

[Pender1]

My K5 has an aftermarket 350 in it that I'm guessing was put in sometime in the 90's, and an edlebrock carb. It was running pretty good when I bought it, but it very shortly blew a head gasket. I replaced it and put the engine back together. This is where the trouble started.

To get it to run I'm at 20ish degrees btc which is giving me about 5" Hg. Turning the idle screws seems to have little to no effect on rpm or vacuum. I can turn both screws all the way in and it keeps running. The engine lugs and dies if I advance my timing any closer to tdc than about 15 degrees btc. I have searched for vacuum leaks and can't find one. I have verified timing order. I have cleaned my carb. I have a new battery and a new starter (that has suddenly started sticking). I can get it to idle smooth, but as soon as I put it in gear, it drops rpm and dies.

Please, I'm begging for someone to tell me what I'm missing. I've done everything I know to do.

[B. W.]

The first thing I would do is check compression. Your blown head gasket has me concerned. You want to make sure your engine is mechanically sound first.
I was taught "Never try to tune a dead horse". I have wasted many hours trying to make blown up engines run - even after being taught otherwise, guess I'm a slow learner! Anytime I have a problem like this I always go back to the basics. I know I sound like a Negative Nancy & I hope your motor is OK.

[68gmsee]

If it was running fine before replacing the head gasket and now it's not, you should first go back to the beginning and start by making sure the distributor was stabbed back in correctly -engine at exact TDC with number one piston at the top of travel on compression stroke. Rotor should be pointing to number one cylinder on the cap. Double and triple check the firing order. If correct, try to readjust the lifters. See if that helps.

Vacuum leaks usually are a problem when the intake end gaskets slip and don't seal properly so check those also.

[geezer#99]

Originally Posted by Pender1

My K5 has an aftermarket 350 in it that I'm guessing was put in sometime in the 90's, and an edlebrock carb. It was running pretty good when I bought it, but it very shortly blew a head gasket. I replaced it and put the engine back together. This is where the trouble started.

To get it to run I'm at 20ish degrees btc which is giving me about 5" Hg. Turning the idle screws seems to have little to no effect on rpm or vacuum. I can turn both screws all the way in and it keeps running. The engine lugs and dies if I advance my timing any closer to tdc than about 15 degrees btc. I have searched for vacuum leaks and can't find one. I have verified timing order. I have cleaned my carb. I have a new battery and a new starter (that has suddenly started sticking). I can get it to idle smooth, but as soon as I put it in gear, it drops rpm and dies.

Please, I'm begging for someone to tell me what I'm missing. I've done everything I know to do.

Are you plugging off your vac advance when you're setting your timing?

[cadillac_al]

Originally Posted by Pender1

I can get it to idle smooth, but as soon as I put it in gear, it drops rpm and dies.

That is the classic symptom of a big vacuum leak. I would start plugging every vacuum connection, even the PCV, to see if you can get some vacuum and a lower idle. Your timing mark may not be correct too. You should verify tdc.

[Pender1]

Originally Posted by cadillac_al

That is the classic symptom of a big vacuum leak. I would start plugging every vacuum connection, even the PCV, to see if you can get some vacuum and a lower idle. Your timing mark may not be correct too. You should verify tdc.

I'll go back through the process of eleminating vacuum accessories. I have verified the mark on my balancer with a cylinder stop.

[cg285]

why don't we start with the symptoms that lead to a "blown head gasket". are we saying that it had a "blown head gasket" and ran just fine?

[Pender1]

Originally Posted by cg285

why don't we start with the symptoms that lead to a "blown head gasket". are we saying that it had a "blown head gasket" and ran just fine?

It ran "Ok". When I bought it there was a small leak between one of the cylinders and one of the coolant passages. It lead to coolant being pumped out of the overflow reservoir, but not at a rate that made it undrivable, just had to keep a jug with me and top it off every other day or so. I drove it to a friend's place a little over an hour away one day and it busted completely, had to pull over 3 times and refill just to get home. I pulled it and there was a little chunk missing in the gasket (I've got a picture of that somewhere). It's not a young engine by any means and I chocked it up to just being old and not the best cared for.

edit: Here's the picture.

[cg285]

my first thought is you have a big vacuum leak (should be easily found) OR perhaps you are not on #1 cyl when checking the timing? what happens if you ramp up the timing further than the 20 you see? i assume it has a severe lack of power? (retarded timing)

today (alone) i had 3 customers swear that something was so and after checking 3 left embarrassed. just saying

[Pender1]

Originally Posted by cg285

my first thought is you have a big vacuum leak (should be easily found) OR perhaps you are not on #1 cyl when checking the timing? what happens if you ramp up the timing further than the 20 you see? i assume it has a severe lack of power? (retarded timing)

today (alone) i had 3 customers swear that something was so and after checking 3 left embarrassed. just saying

I'm 100% positive that I'm using the right cylinder for my timing check. I don't know if I have a lack of power or not, the whole problem is I can't put it in gear without it dying.

[cg285]

Originally Posted by B. W.

The first thing I would do is check compression. Your blown head gasket has me concerned. You want to make sure your engine is mechanically sound first.
I was taught "Never try to tune a dead horse". I have wasted many hours trying to make blown up engines run - even after being taught otherwise, guess I'm a slow learner! Anytime I have a problem like this I always go back to the basics. I know I sound like a Negative Nancy & I hope your motor is OK.

in my early days at the dealership if we tuned an engine and afterwards found that it had other issues (no compression, etc) we didn't get paid for that job.
probably can't do that these days though

[cg285]

Originally Posted by Pender1

I'm 100% positive that I'm using the right cylinder for my timing check.

i saw that movie about an hour ago from one of my employees :-)

but let's say that is correct and your timing tab/balancer is correct then start looking for a vacuum leak. you can spray a lot of stuff like wd40, propane, carb cleaner.... around the intake/head and carb base to see a change in rpm. any hose fittings should be obvious. pinch off to verify. if you can't come up with anything put a vacuum gauge on the dipstick and see what it reads. this is in case the intake gaskets are damaged and leaking internally. you would have had to work at it if the gaskets were mis-positioned tho'

one more thing: rev the engine up and hand close the choke until it almost dies. do that a couple times and see if there is a change

[franken]

If I recall the right plug wire to check timing is 1 which is front driver's side. Whenever I'm 100% sure I know that's the problem.

[Pender1]

Originally Posted by cg285

but let's say that is correct and your timing tab/balancer is correct then start looking for a vacuum leak. you can spray a lot of stuff like wd40, propane, carb cleaner.... around the intake/head and carb base to see a change in rpm. any hose fittings should be obvious. pinch off to verify. if you can't come up with anything put a vacuum gauge on the dipstick and see what it reads. this is in case the intake gaskets are damaged and leaking internally. you would have had to work at it if the gaskets were mis-positioned tho'

one more thing: rev the engine up and hand close the choke until it almost dies. do that a couple times and see if there is a change

What will reving and closing the choke accomplish?

[cg285]

we won't know until you try it. it sometimes fixes stuff
try it 3 or 4 times agressively

[Port&PolishMan]

Originally Posted by Pender1

My K5 has an aftermarket 350 in it that I'm guessing was put in sometime in the 90's, and an edlebrock carb. It was running pretty good when I bought it, but it very shortly blew a head gasket. I replaced it and put the engine back together. This is where the trouble started.

To get it to run I'm at 20ish degrees btc which is giving me about 5" Hg. Turning the idle screws seems to have little to no effect on rpm or vacuum. I can turn both screws all the way in and it keeps running. The engine lugs and dies if I advance my timing any closer to tdc than about 15 degrees btc. I have searched for vacuum leaks and can't find one. I have verified timing order. I have cleaned my carb. I have a new battery and a new starter (that has suddenly started sticking). I can get it to idle smooth, but as soon as I put it in gear, it drops rpm and dies.

Please, I'm begging for someone to tell me what I'm missing. I've done everything I know to do.

Your Running Off of the Transition Port to much which - Means the Linkage
got Moved Bent or hooked up Differently ( Spring ) etc.

I always take Pictures of anything I dismantle - Today - that is the easy Part . Remembering after two or three weeks go by - Due to other Daily activity or just Time to get Proper Parts with Over Loaded Lifestyles - many have to endure . .

I have a Memory like an Elephant - but still do the above as 100 % Q. C

That said - Head Gasket - I take it You just over Heated Motor - Towing ?
Check . .Compression as other said is Very Good - back to Basic's . .

Reason I ask - trying to - Eliminate Running Lean Condition .. from Before ?

PS : If this Carburetor has No Transition Ports , then Vacuum Leak Checking.
( I do that with a Spray Can of Carburetor Cleaner ) around Intake Area's - Engine will Stumble - Sucking in any Cleaner .
Pin Point the Area . .

[geezer#99]

Originally Posted by Port&PolishMan

Your Running Off of the Transition Port to much which - Means the Linkage
got Moved Bent or hooked up Differently ( Spring ) etc.

I always take Pictures of anything I dismantle - Today - that is the easy Part . Remembering after two or three weeks go by - Due to other Daily activity or just Time to get Proper Parts with Over Loaded Lifestyles - many have to endure . .

I have a Memory like an Elephant - but still do the above as 100 % Q. C

That said - Head Gasket - I take it You just over Heated Motor - Towing ?
Check . .Compression as other said is Very Good - back to Basic's . .

Reason I ask - trying to - Eliminate Running Lean Condition .. from Before ?

PS : If this Carburetor has No Transition Ports , then Vacuum Leak Checking.
( I do that with a Spray Can of Carburetor Cleaner ) around Intake Area's - Engine will Stumble - Sucking in any Cleaner .
Pin Point the Area . .

What's a 'transition port'?

[kwmech]

How did you adjust the valves? and are you sure of the firing order

[cadillac_al]

That's a good question about the valves. The valves can be out of whack;especially if you are using the twist-the-push-rod technique for the first time. A compression test might have picked that up.