1984 Chevy C-10 Pick Up Hard To Start and Stop Engine

[gconn77]

I wasn't quite sure if I should have created this post here or in the Engine & Drivetrain section. If it needs to be moved, sorry about that? It was a toss up there?

I have an 84 Chevy C-10 pickup truck. It has a 305 and a 3 speed auto trans. The engine and trans are not original. Thru different people telling me, it was possible that the engine originally was TBI and I had a 4 speed.

At anyrate... I have done a lot to keep this old truck running... and it does do fine. It is my daily driver locally to work. But I do have a little trouble I would like some suggestion on.

The truck is pretty hard to start... I have installed a manual choke, and that helps a lot... pretty much satisfied with that... but I do have to let it warm up.. if I don't then it will stall. Additionally, I do have to start it three times before it will stay running on its own.

Second problem... is sometimes it wants to keep running... even after I turn the key off.... after turning the key... it will seem like it tries to keep going... missing and spitting... and then finally shuts off! LOL!!!

So, I have a few days off work coming up and wanted to work on those issues... If anyone can point me in the right direction that would be great.

There are a few other issues going on as well... but I can talk more in depth about those later... basically after running the truck for awhile... if I turn it off and then try to start it again... its extremely hard to start.... seems like there insn't enough power in the battery or starter to turn the engine... Again, I wanted to deal with the first two problems first.... but felt I should explain this other problem as well just in case that they might be related.

Thanks in advanced for anyone's help!
Regards,
Garry

P.S. Not sure if putting external links here is ok... but I wanted to direct people to a small page I created that has tons of pictures of the truck... if links are not allowed, please remove and accept my appology.

More Info on my 1984 Chevy C-10 Pick Up Truck

[Prerunner1982]

1st problem, have to restart before it will stay running... sounds like perhaps your carb isnt set right, the engine should run at alittel higher rpm than idle until its warm, to keep it running. then when warm you can kick it down.. mine doesnt work as well... i also have to restart mine a few times..

2nd.. sounds like it may be a timing problems and it is causing it to diesel...

3ed.. hard to restart... what does it do? click? turn over slowly? nothing? it could be the start is getting to hot, common problem.. after it cools it will start fine...

i am by far no expert.. so hopefully one of the more knowledgable members (old timers ) will step in and shine some more light on this..

[piecesparts]

Hard start----choking the engine to much will cause it to start and then die, due to not enough air through the carb. The fact that it dies, also can be attributed to the idle speed not high enough. You having to let it warm up before moving it, could again be tied to the choke setting being to much. The starting and the dieseling could be tied to the timing of the motor. Do you have a timing light? If so, what did you set your timing at, and did you set it with the distributor vacuum line removed. Are you still using the computer distributor, or has it been changed out for an earlier HEI distributor? The computer controlled distributor has a plug that needs to be unplugged to time the motor and in most cases it will not adjust past the recommended setting very well. I'm betting your timing is the major problem here.

If you are running an HEI or an aftermarket distributor that does not have the computer connected, then check to see if your timing is around 8 to 10 degrees BTDC and then connect the vacuum line and the timing setting will change. If the setting doesn't change then your distributor vacuum pull-off or the weights inside are bad or hanging up.

[gconn77]

Originally Posted by Prerunner1982

1st problem, have to restart before it will stay running... sounds like perhaps your carb isnt set right, the engine should run at alittel higher rpm than idle until its warm, to keep it running. then when warm you can kick it down.. mine doesnt work as well... i also have to restart mine a few times..

2nd.. sounds like it may be a timing problems and it is causing it to diesel...

3ed.. hard to restart... what does it do? click? turn over slowly? nothing? it could be the start is getting to hot, common problem.. after it cools it will start fine...

i am by far no expert.. so hopefully one of the more knowledgable members (old timers ) will step in and shine some more light on this..

I am leading to believe that this truck originally had TBI or some kind of fuel injection system. A friend of mine suggested that because there are so many holes that I have plugged and capped off. He suggested that someone possibly did an engine swap... if not that at a minimum removed the TBI kept the existing intake manifold and slapped a quadra jet on it.

Look at this image below:



See the little rubber hose with a bolt stuck in it? I few months ago, I replaced that little rubber hose with a bolt stuck in it with a rubber cap. Now today, I checked that rubber cap, and it was cracked... letting tons of air in. I replaced that cracked/broken rubber cap with a new one. In addition to that... I replaced all the spark plugs.The old ones were very nasty. The tips were all somewhat chalky white... and there was tons of oil on them... it was hard to tell... but most of the oil was caked on the threads... the engine does leak oil... from many places... (again... another problem I will work on.. but one thing at a time! LOL!!!) so I think somehow oil seeps in from the outside and just works its way in thru the threads. I don't think that the engine is burning oil... my exhaust is not very smokey at all... However, I am aware that my rings might be wearing. I did a compression test and the pressure started at 90 and then increased to a max of 120 after the second complete stroke... these readings were all the same within 2 to 4 lbs. Reading in the Chiltons... it tells me that after the first stroke cycle.. if the first reading is lower and then increases after the second stroke cycle and remains consistant after that... then that indicates that your have rings that are wearing out. To me, that seems that my engine is not quite worn out.... perhaps mid-life, maybe a little less? Eitherway... the engine isn't smoking or burning oil... from what I can tell...

Replacing the rubber cap and spark plugs... the engine seems to shut off better now. I am not sure if this COMPLETELY fixed that problem... but it does seems to cut off better... it doesn't act like it wants to keep running. I am thinking that rubber cap has more to do with it than the plugs... but I thought I would mention that as well.

The starter... yes, I believe that you are right.... after the engine is hot from being run awhile.... if I turn it off, and attempt to restart the engine.... it is very slow to turn over.... between the stroke cycles... it seems that the starter struggles to make it past the compression stroke... it can easily get stuck at the compression stroke and not be able to turn the engine past that stroke cycle.... waiting a few minutes... I can try again... and it might have enough power to turn it past that cycle... and turn the engine again very slowly all the way thru but quickly loose power and become able to turn the engine again.... waiting about 30 minutes... has more power.... waiting after an 8 hour day at work.... fine, turns the engine over very quickly.. has a lot of power.

So... maybe I should get a new starter.... that leads to another problem that I will discuss in more detail later.... but all the elecrtical wires are totally rigged up/ spliced, duct taped... etc.. I can take some photos and create a seperate post cover that problem later. I just wanted to mention it here briefly just in case it could be related to this problem.

Along with that... my carb had some issues as well... the electric choke was broken and or damaged. I replaced it with a manual choke and ran the cable into the cab, and mounted it near the headlight knob. Now... unfortunately, in the past, I never owned a carborated automobile aside from now owning this truck. So I am not sure if this is normal... but in order for me to pull the choke knob out all the way, I have to tap the gas peddle while pulling the choke knob. After starting the engine... it will idle high... I would guess 1800 to 2000 RPM's... I don't have a tac, but can take a stab at guessing. Now, I can let it run like this forever... (after restarting it three times). In order for me to get the engine to idle lower.... I have to give the gas peddle a good tap... giving the engine a little jolt of power. From there... some how it releases something and then the engine will idle normal. I don't know if this is normal.... it actually works out quite well for me though... in the morning, I go out... start the truck... go back inside, gather my things for work... go back out about five minutes later.... engine still in a high idle... and truck is warmed up.

Prerunner1982, thanks for the feedback and your help. I look forward to hearing back from you after reading my response.

Originally Posted by piecesparts

Hard start----choking the engine to much will cause it to start and then die, due to not enough air through the carb. The fact that it dies, also can be attributed to the idle speed not high enough. You having to let it warm up before moving it, could again be tied to the choke setting being to much. The starting and the dieseling could be tied to the timing of the motor. Do you have a timing light? If so, what did you set your timing at, and did you set it with the distributor vacuum line removed. Are you still using the computer distributor, or has it been changed out for an earlier HEI distributor? The computer controlled distributor has a plug that needs to be unplugged to time the motor and in most cases it will not adjust past the recommended setting very well. I'm betting your timing is the major problem here.

If you are running an HEI or an aftermarket distributor that does not have the computer connected, then check to see if your timing is around 8 to 10 degrees BTDC and then connect the vacuum line and the timing setting will change. If the setting doesn't change then your distributor vacuum pull-off or the weights inside are bad or hanging up.

piecesparts, please look at the photo above and the two photo below to help me identify what kind of distributor I have:





I do not have a timing light. I am interested in purchasing one and think I might get one next time I am at the auto parts store. I hope that these photos help you better help me! I look forward to hearing back from you after you read my response.

Guys... thanks again for your feedback. You guys were very quick to send me a reply. Thanks!

Garry

[pebbleboy]

Thats a HEI

[gconn77]

Originally Posted by pebbleboy

Thats a HEI

and...

Originally Posted by piecesparts

I'm betting your timing is the major problem here.

If you are running an HEI or an aftermarket distributor that does not have the computer connected, then check to see if your timing is around 8 to 10 degrees BTDC and then connect the vacuum line and the timing setting will change. If the setting doesn't change then your distributor vacuum pull-off or the weights inside are bad or hanging up.

Ok... now that I know that this is an HEI. Can you guys respond with some links to other posts that explain more on checking and setting your timing, and give me some additional information on setting the timing around 8 to 10 degrees BTDC.

I appreciate everyone's help!

Garry

[pebbleboy]

Originally Posted by gconn77

and...



Ok... now that I know that this is an HEI. Can you guys respond with some links to other posts that explain more on checking and setting your timing, and give me some additional information on setting the timing around 8 to 10 degrees BTDC.

I appreciate everyone's help!

Garry

Did you replace fuel filter and check/replace spark plugs? I'd start there Mine ran a little rough till that.

[gconn77]

Originally Posted by pebbleboy

Did you replace fuel filter and check/replace spark plugs? I'd start there Mine ran a little rough till that.

I have not replaced the fuel filter... and as stated above, I did change the plugs tonight and do notice an improvement.

[piecesparts]

I still think that your starting problem is the timing. Especially the hard crank over part where your starter won't quite make a full crank. That is an indication that it is way advanced, in my book. Yes that distributor is an HEI and that will simplify things some. Not knowing your mechanical background, excuse me if I tend to get to in depth as to what you need to do. Have you put on a new cap and rotor lately? If not, I would look into doing that. While you are in the distributor lightly oil the weights on the centrifugal advance unit. That is the part of the distributor shaft directly below the rotor. Those weights can get a little rusty and hang up when you are running the motor. Once you have the distributor back together, then pull the vacuum line off of the advance dashpot and put a small bolt in that rubber line, to plug the vacuum leak while your timing the motor. Get a 9/16 wrench and loosen up the distributor hold down bolt at the base of the distributor, DO NOT TURN THE DISTRIBUTOR, YET. Locate the timing marks on this motor (in this case I would look straight down in front of the timing chain cover behind the water pump and see if it is there). Clean the tab off so that you can see the numbers and the pointers, also go underneath the truck and put some white or silver paint in the groove of the harmonic balancer so that it is easy to see when you time the motor. You may have to rotate the motor until it comes into sight. Buy or borrow a timing light and connect it to the #1 spark plug wire and start the motor. Once the motor is running set the light on the tab for the timing marks and see if you can see the timing mark align with something on the tab. There will be a "0" mark and then indications of BTDC and some after the TDC which is the "0" mark. I used to set my timing at 10 or 12 degrees on a motor with an HEI and it worked fine for me. I do things a little different now, but it is complicated and I use a timing light with a built in advance unit. For what you are trying to accomplish, lets get the base timing first. After you set the timing, then tighten the 9/16 bolt and check it again, to make sure it didn't move while you were tigthening the bolt. Then re connect the vacuum line from the carb to the distributo dashpot and look to see if the timing line moves, it should.

The vacuum fitting that you put the cap on is not a serious problem, leave it capped off for now.

[SSC's76]

Sounds like the timing is off or you have some major carbon buildup problems. Like mentioned check the timing verify that it isnt too advanced or just for kicks back it off a tad and see what happens. If that doesent work check your parts stores for a Berrymen top end cleaner kit and give that a shot. With carbon buildup in your cyl's it creates hot spots. When it gets real bad these hot spots ignite the fuel without spark causing a run on dieseling effect.

[82c10]

it was not a TBI engine originally, the 1st year for them in our trucks was 87

[SlapFish]

I thought it was '86. Either way, it wasn't TBI.

Also, is the engine from a camaro? If so, it may need a higher grade of fuel. I upgraded my truck's 305 camaro engine to higher grades of fuel and I noticed my "dieseling" problem go away.

[82 Silverado 4X]

One thing I noticed in your photo is that your carb has an electronic throttle stop solonoid (I beleive that is the correct name). It's the small canister with the single wire going to it with what should appear to be a bolt coming out of the end on the drivers side of the carb. This solonoid is supposed to extend its bolt when the key is in the on position to open the throttle plates slightly to control your idle speed. It retracts when the key is shut off and closes your throttle plates. If it had stopped working at some point, someone may have screwed the bolt out to try to control the idle. If this is the case your truck may try to stay running after you shut it off. You can test the solonoid easily by having someone turn the key from the off to the on position while you hold the throttle plate open slightly. The solonoid should extend when the key is in the on position and retractwhen it is turned to off.
It was just a thought.

[piecesparts]

The comment that the plugs are covered with oil indicates one of two things. The valve guides are leaking oil, which is very common or the rings are getting bad. You stated that your compression showed around 125 pounds or so on all of the cylinders, so I am guessing the valve guides. Oil seeping in through the plug threads is not an option (If it was then you would have exhaust leaking out when the motor is running. The plugs on a Chevrolet have a tapered seat to seal them and that should not be where your problem is. I agree with the idea of cleaning the top end, but if you can't find a "Berryman Top End Cleaning Kit" you can use some auto tranny fluid and slowly dump it down the carburetor as you are reving the engine. You have to keep the motor running so it may require some high RPMs. after you have dumped the fluid down the carb let it set for awhile and soak, then start the truck and drive it until the exhaust clears. If you live in a suburban area, I would find a rural place to do this. The SMOG Cops will hate you for about 15 minutes or so. It really looks bad until the motor flushes clean of the fluid.

[Prerunner1982]

82 silverado 4x, i was always told that was for the A/C. When the A/C was on that would kick up the idle so the engine wouldnt die at lights and such..

gconn, i will read all your replies later, have things to get to tonight..

[84 400]

i am in a similar situation. mine starts easy with a push of the gas peddle and every now and again wants to run on after the key is off. any way this all on the 1985 305 silverado that is now getting used as my other truck is away for the winter. The PO owner removed the egr and the charcoal canister before i got the truck. but it failed its inspection so i must undo what he did and make it leagal agian. First off did the 305 have a belt driven air pump? also does any one have a good digram of how this systom is set up ??? thanks

[82c10]

Originally Posted by Prerunner1982

82 silverado 4x, i was always told that was for the A/C. When the A/C was on that would kick up the idle so the engine wouldnt die at lights and such..

gconn, i will read all your replies later, have things to get to tonight..

it is for the a/c, it is called i believe an "idle compensator" to raise the idle up when the a/c is on, some people wire them to switches to make them idle higher when they first start there vehicle up also

[gconn77]

Originally Posted by 84 400

i am in a similar situation. mine starts easy with a push of the gas peddle and every now and again wants to run on after the key is off. any way this all on the 1985 305 silverado that is now getting used as my other truck is away for the winter. The PO owner removed the egr and the charcoal canister before i got the truck. but it failed its inspection so i must undo what he did and make it leagal agian. First off did the 305 have a belt driven air pump? also does any one have a good digram of how this systom is set up ??? thanks

I am not sure if this helps or not... but I have taken this photo many months ago and put it on my website. See image below and click on it for a large view:



and... this is where I am at with it up-to-date:


I have quite a few photos pertaining to the emissions... I too was attempting to get everything back to factory spec... I am not quite there... nor am I all that motivated anymore... LOL!!! there is no emission testing where I live. I just suffer a little bit being unconscious of the enviroment... right! Anyway check out that photo and if you like check out the page I made for my truck... it might help.

[MylilBowTie]

Do you still have the choke wire disconnected?

[84 400]

thanks man for the pick but yours has the caps on it and i don't know were the hoses go. also did mine have an air pump that was belt driven????