327c.i. Sbc running rough, advice needed

[Bullett]

Starting to get really discouraged now. Bought a new (good quality) distributor cap and installed, it didn't help. #2 cylinder still isn't working. The exhaust manifold on that particular cyl. Is far colder than the rest. I then swapped plug wires with another cylinder and #2 cyl. Still didn't work. I am starting to think the worse now. Bj383's theory is my next route. What else could it be. Could a bad rotor button possibly do this? Bad distributor? If I had a broken piston ring, I wouldn't think I would get the 150 psi cyl. Pressure, which is the same as #4 cyl. If it turns out to be something internal, I'm not going to go there, I will just keep my eyes open for a different motor altogether. Preferably one with HEI ignition and 4 barrel carb.

[bj383ss]

Its worst case scenario. The problem on these older style engines with flat tappet cams is all the existing motor oil has had the zinc removed because it causes pollution. New engines with roller cams dont require the zinc. So you have to use a Zinc additive. My 383 was completrly rebuilt had less than 3,000 miles on it. I had 4 lobes that were completely flat and several others on there way. I had a Comp cams xe268 cam which has more aggressive lobes to open the valves faster. It took me almost a year to figure out what was wrong


I'm hoping the best for you


Bret

[Bullett]

Well, guess buying a vehicle sight unseen off Ebay probably wasnt a good idea. The strange thing is that when i got it, ibesides starting hard because of no choke, it ran idled fine. I never drove it because it was mid winter. I thought for sure this had something to do with the motor getting wet. Oh well, it is what it is i guess.

[Ken Magura]

Originally Posted by AcampoDave

Hey Ken, welcome to the forum.

Thank you for the welcome !!
I've been hanging around for a while and really enjoy reading a lot of good information from the members here.
KM

[Ken Magura]

Originally Posted by Bullett

Starting to get really discouraged now. Bought a new (good quality) distributor cap and installed, it didn't help. #2 cylinder still isn't working. The exhaust manifold on that particular cyl. Is far colder than the rest. I then swapped plug wires with another cylinder and #2 cyl. Still didn't work. I am starting to think the worse now. Bj383's theory is my next route. What else could it be. Could a bad rotor button possibly do this? Bad distributor? If I had a broken piston ring, I wouldn't think I would get the 150 psi cyl. Pressure, which is the same as #4 cyl. If it turns out to be something internal, I'm not going to go there, I will just keep my eyes open for a different motor altogether. Preferably one with HEI ignition and 4 barrel carb.

Bullett: I understand your frustration. As I read your initial post about the truck running good and then the water hitting it, one would naturally assume the ignition system was damaged. The first thing I would always look for is the cap and rotor. I grew up with these motors like so many of you have and have replaced many cap and rotors from vehicles hitting water on the highway and splashing the ignitions causing a temporary mis-fire and thus cracking a cap or rotor.
Do you have any history on the truck? and by the way, it's very nice!!
I just think it is a little unusual for a motor to develop internal problems from splashing water on it.
KM

[Bullett]

Originally Posted by Ken Magura

Bullett: I understand your frustration. As I read your initial post about the truck running good and then the water hitting it, one would naturally assume the ignition system was damaged. The first thing I would always look for is the cap and rotor. I grew up with these motors like so many of you have and have replaced many cap and rotors from vehicles hitting water on the highway and splashing the ignitions causing a temporary mis-fire and thus cracking a cap or rotor.
Do you have any history on the truck? and by the way, it's very nice!!
I just think it is a little unusual for a motor to develop internal problems from splashing water on it.
KM

I don't have any history on the truck, I live in Maine and bought the truck on Ebay, it came from Tenn. I am quite certain the PO told me that it was a crate motor with relatively low mileage. I tend to believe that due to his honesty with everything else on the truck. The motor "looks" like a low mileage motor and neither the motor or tranny leak so much as a drop of oil. I pulled the exhaust manifold off 1 side of motor, just to check the gasket on #2 cyl. , and even the manifold studs looked fairly new. The motor doesn't smoke any. I wish I would have run the truck a little when I got it in Dec. but I only ran it off the car carrier and into my garage. Again, besides being cold blooded, it idled fine once the motor got up to temp. I have basically been working on it all spring, new wiring harness, new bed wood kit, new headliner and interior carpet, etc...when the top of the motor got wet, it immediately ran real rough and did some major backfiring up through the carb. I though if I just keep running the motor, it will eventually dry out and be o.k. Again. As I ran it, it didn't get any better. I eventually got on line and found where people with a wet motor use WD 40 to disperse the water, that is what I did and it did run some better. I then sprayed everything again and repeated a couple more times until it ran pretty good except wouldn't idle and stalled anytime I tried to put it in gear. Through a bunch of head scratching, I narrowed it down to #2 cyl. But, again, turning the truck over with #2 & #4 spark plugs out but still connected to plug wires, both cyl. Have similiar looking spark??? So basically, that cyl. Is getting fire but still isn't working. I am thinking things are looking pretty bleak. I am wondering if I did something to the motor while running it while trying to dry it out. It was back firing pretty violently. I'll kick myself if I damaged the motor. That is all I know about it. I am thinking if the violent back fires did something to that particular cyl., it wouldn't have as good of cyl. Pressure as the rest, but, again, it has 150 psi, just as the cyl. Beside it???

[Ken Magura]

Originally Posted by Bullett

I don't have any history on the truck, I live in Maine and bought the truck on Ebay, it came from Tenn. I am quite certain the PO told me that it was a crate motor with relatively low mileage. I tend to believe that due to his honesty with everything else on the truck. The motor "looks" like a low mileage motor and neither the motor or tranny leak so much as a drop of oil. I pulled the exhaust manifold off 1 side of motor, just to check the gasket on #2 cyl. , and even the manifold studs looked fairly new. The motor doesn't smoke any. I wish I would have run the truck a little when I got it in Dec. but I only ran it off the car carrier and into my garage. Again, besides being cold blooded, it idled fine once the motor got up to temp. I have basically been working on it all spring, new wiring harness, new bed wood kit, new headliner and interior carpet, etc...when the top of the motor got wet, it immediately ran real rough and did some major backfiring up through the carb. I though if I just keep running the motor, it will eventually dry out and be o.k. Again. As I ran it, it didn't get any better. I eventually got on line and found where people with a wet motor use WD 40 to disperse the water, that is what I did and it did run some better. I then sprayed everything again and repeated a couple more times until it ran pretty good except wouldn't idle and stalled anytime I tried to put it in gear. Through a bunch of head scratching, I narrowed it down to #2 cyl. But, again, turning the truck over with #2 & #4 spark plugs out but still connected to plug wires, both cyl. Have similiar looking spark??? So basically, that cyl. Is getting fire but still isn't working. I am thinking things are looking pretty bleak. I am wondering if I did something to the motor while running it while trying to dry it out. It was back firing pretty violently. I'll kick myself if I damaged the motor. That is all I know about it. I am thinking if the violent back fires did something to that particular cyl., it wouldn't have as good of cyl. Pressure as the rest, but, again, it has 150 psi, just as the cyl. Beside it???

I really don't think you've damaged that motor to any serious degree if any. Did you pull the valve covers to check push rods or valves? Did you check the firing order to make sure you didn't cross your plug wires while checking it before? Sounds like you described a pretty good motor. All the indications of a fresh motor I would say. It just seems to me from your describing your problems it is close to ignition problems or something closely related.
KM

[Bullett]

Haven't pulled valve cover yet, I will do that tomorrow, hopefully it can find something relatively simple. Thanks for the advice.

[Ken Magura]

Originally Posted by Bullett

Haven't pulled valve cover yet, I will do that tomorrow, hopefully it can find something relatively simple. Thanks for the advice.

Might have bent a pushrod or two !!
KM

[AcampoDave]

Originally Posted by Bullett

Starting to get really discouraged now. Bought a new (good quality) distributor cap and installed, it didn't help. #2 cylinder still isn't working. The exhaust manifold on that particular cyl. Is far colder than the rest. I then swapped plug wires with another cylinder and #2 cyl. Still didn't work. I am starting to think the worse now. Bj383's theory is my next route. What else could it be. Could a bad rotor button possibly do this? Bad distributor? If I had a broken piston ring, I wouldn't think I would get the 150 psi cyl. Pressure, which is the same as #4 cyl. If it turns out to be something internal, I'm not going to go there, I will just keep my eyes open for a different motor altogether. Preferably one with HEI ignition and 4 barrel carb.

Why not just take it to a professional mechanic? ! There is no shame in turning to a pro for at least a diagnosis. You might end up money ahead in the end.

[chevy_mike]

Moved to Engine forum as this is the appropriate place for this thread.

[Bullett]

Originally Posted by AcampoDave

Why not just take it to a professional mechanic? ! There is no shame in turning to a pro for at least a diagnosis. You might end up money ahead in the end.

I always like to try everything I can before I pass it on to the professionals, this is the best way to learn new things for me. I really havent spent much of any money yet, so self diagnosing and repairing is always what I try to do first. If the push rods and valves look fine, I will probably end up bringing to a garage.

[Bullett]

Pulled valve cover and pulled the 2 pushrods to that particular cyl., and unfortunately they were both fine. Rocker arms looked the same as the rest of them. BJ383, how did you measure your cam lobes? I'm guessing a dial indicator on top of springs? Then you must measure the rest and then compare? Now I am to the point, do I bother taking it to a pro, is there much left I haven't checked for? Or do I buy a good running 355 motor from a friend of a friend. Motor is complete from 4 barrel to oil pan and even has alternator starter, flywheel etc...I believe I can get it for $450. That is the beauty of the Sbc motors, they are very plentiful and quite cheap. Supply and demand theory I guess. I guess I am thinking, if it is an internal issue, I don't want to put any money in it, I would just as soon buy the 355 that I know runs fine. Just thinking out loud here.

[AcampoDave]

Are you 100% sure your firing order is set and the timing is perfect. I'm still thinking something is off in that regard. You already re-arranged 2 wires and that speaks volumes to your troubles. Seriously, bring that thing to t.d.c and set that distributor up right. I would come and help you but my lear jet needs a new timimg chain right now. Edit: and I repeat that 2 bolts holding a carb down seems problematic to me.

[Bullett]

The firing order is correct as far as the firing order schematic I found online, but again, I am not even sure what decade the motor comes from. I am gonna make appt. for it at a garage in town that seems to do a lot with old stuff. The top dead center and timing require tools and knowledge I don't have. I have decided I am going to have it looked at before I go to plan B. I'll post as I find anything out but I suspect it will be next week. I am getting really anxious to drive the dang thing.

[AcampoDave]

Originally Posted by Bullett

The firing order is correct as far as the firing order schematic I found online, but again, I am not even sure what decade the motor comes from. I am gonna make appt. for it at a garage in town that seems to do a lot with old stuff. The top dead center and timing require tools and knowledge I don't have. I have decided I am going to have it looked at before I go to plan B. I'll post as I find anything out but I suspect it will be next week. I am getting really anxious to drive the dang thing.

Good call, a 327 is a classic and you're making a wise decision.

[bj383ss]

My cam lobes were so flat that when I turned the engine over by hand with a big ratchet on the crank bolt, the #7 cyl & 8 rockers didn't even move! If you rotate the engine and see all the rockers moving then you are fine. You say you don't know enough to get it on top dead center.

Its pretty easy. Pull the #1 spark plug. Take the gauge off your compression tester and just screw the hose into the #1 cylinder so you can here when it comes up to compression. It will make a woosh sound. Your timing mark on your balancer should be close to TDC mark. You can move the engine right on with a big breaker bar on the crank bolt.

Make a mark on the base of your distributor with a sharpie or piece of tape right below the #1 terminal so you can see where your rotor is in relation.

Once you have this done pull the distributor cap and see where the rotor is facing. It should be pointing to the #1 terminal which is pointed towards the #1 cylinder on the block incidentally. If the rotor is facing towards the firewall you are 180* off. The distributor will need to be pulled and set back in so it faces #1 terminal.

Again it seems strange that this would only come to light after some water sprayed on the engine.

Bret

[Coley]

Ok, here is quick, easy test to find out if you have a bad cylinder, wire or spark plug.
Pull all of the boots up on the spark plug wires where they go into the distributor, well clear of the ends where they fit over the distributor input 'nubs'....leave the wires plugged in tho'.
Now, you should be able to see the the connections between the spark plug wire ends and the (8) receiver cups in the distributor.
Now, find-get a 12 volt electrical tester (the kind with the light in it, an aligator clip on one end and a pointy end on the other).
Properly/correctly ground that tester to something like the brake booster mount bolt or similar.
NOW, one at a time insert the pointy end down into each of the (8) distributor/wire connector holes and NO you won't get 'zapped'.
Everytime you insert that tester in there you should hear and feel a noticeable 'drop' in the way the motor runs. This is because you have shorted out that cylinder from operating.
Go around all (8) plugs/cylinders and mark the cylinders/wires where it made no or very little difference. These are your problem cylinders and the problem is either the plug, the wire or the cylinder itself....but at least you'll know which cylinders are causing you grief.
Ok...thats it for the moment...give it a try.
Coley

[Bullett]

Thanks fellas for all the good tutorials, as scary as it sounds, it actually makes good sense to me. I am leaving for a fishing trip in the morning, when I get back Sunday night, I am gonna give this stuff a try. Thanks...Bullett

[burnin oil]

As said pull the valve covers. Have someone spin the motor over for you. Watch all the rocker arms and see if everything is moving the same amount. If a rocker is moving less then you found the problem. The cam is flat. If everything still looks good Try backing off the the rocker arms a 1/4 turn. Odds are the motor has a hydraulic cam and the valves may be set to tight. If the rocker now flops around alot then you have a solid cam and you will need to stop and reset that valve lash. On a hydraulic cam when the lifters pump up they can lift the valve off the seat. This is only a test. If it works better then a reset of the valves is needed. Sounds stupid but I have been bit that way before. Sometimes lifters jst dont want to pump up initially and end up to tight. Another thought that doesn't deal with the cylinder problem but the idle is your points. Do you know how to set them? Most new points sets are junk and dont work very well. When I first got my 72 it still had its original distributer in it with points. They needed adjusted like every two weeks to componsate for wear, not just checked at oil change.

[geezer#99]

Originally Posted by AcampoDave

Good call, a 327 is a classic and you're making a wise decision.

That's a very true statement. The 327 was an awesome motor even in 2 bbl form.
But he doesn't have one. Accessory holes in the head, 305 exhaust manifolds are a couple clues.

[burnin oil]

Good observation. Only thing is the 70s were 40 years ago. How many parts have been swapped out over the years? I used to know a guy that had a late 70s pickup with a nice little 283 in it. Had newer heads with a qjet on top of it. All hooked to a 4spd auto. Looked factory, didn't cost him alot to rering it, and got 20+MPG.

[geezer#99]

Originally Posted by burnin oil

Good observation. Only thing is the 70s were 40 years ago. How many parts have been swapped out over the years? I used to know a guy that had a late 70s pickup with a nice little 283 in it. Had newer heads with a qjet on top of it. All hooked to a 4spd auto. Looked factory, didn't cost him alot to rering it, and got 20+MPG.

Musta been a 283 with 305 heads. I worked with a guy that tried the 283 with 350 (76 cc) heads trick. We had to push it to get it moving in a soft grassy field. Had likely only 7 to 1 compression.

[geezer#99]

Apoligies to Bullett!!
I'm not slamming your truck. Just made an observation on your motor.
Something else to check for you. You seem to be a hands on guy. A very good attribute. Too many cheque writer's out there.
Any where on a sbc where the intake bolts line up with the pushrods (4 spots IIRC) you need to use the correct length bolts. Otherwise a longer bolt could contact the pushrod and cause problems like you're having.

[burnin oil]

Originally Posted by geezer#99

Musta been a 283 with 305 heads. I worked with a guy that tried the 283 with 350 (76 cc) heads trick. We had to push it to get it moving in a soft grassy field. Had likely only 7 to 1 compression.

Good chance that they were. All I really remember was that the heads had 1.94 valves. I am sure that there are a few 305 castings like that back in the day. This was 15-20 years ago. The guy old had a few hundred bucks in the drivetrain and it ran hard, especially for a short stroke in the mtns.