RIP engine? need some good tech.

BullittStangV8

Founding Member
Oct 5, 2002
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Okay guys, im thinking my engine may have gone to the engine heaven, so heres where i need help. First the background. The engine is a 65 289, with stock heads, edelbrock rpm intake, a street deamon carb, a comp cam, and long tube headers. I was driving home and went to do i higher rpm 1-2 shift. Went to let the clutch out in 2nd, and then engine died. I pull over, stop the car and look under the hood. everything appears to be fine. Go to crank it, and it barely wants to start or hold an idle. I limp home, and just keep the rpms up above the stall point. (from idle (700 rpm) to around 1500 rpms. Above that it seems to not die out. Tonight i finally had time to start looking at the problem, and i had a friend turn it on, while i was behind the car. There is a definite miss on the right side bank. The left side i can feel and hear the 4 cylinders firing. (the pulses and audibly) Meanwhile the left side i can only make out 3. Seems like the right side has dropped a cylinder. Great..So now i have to try and hunt down the problem. Im fearing a broken rod, piston, or connection rod. Seems like worn rings wouldnt cause this much of a noticable problem. (i would suspect simply a loss in power for a worn ring) The car does not smoke from either tailpipe, and it has true dual exaust. So now im out to do a compression check to see if anyone of the cylinders isnt making compression.
If i have no compression, what are the possible broken components/reasons why it wont hold compression? It seems that if i find that compression is lost, im going to be tearing the engine down to find the problem. If the compression is fine, what would be other possible reasons for the cylinder dropping? Thanks for any help or feedback guys, i really dont want to loose this engine.
Mike
p.s what kind of fitting will i need to adapt to the compression gauge?
 
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Ussually when you drop you rod or break a piston the car pretty much just stops ;)

Check:

All spark plug wires are intact.
Pull the plugs and inspect
Perform compression test on all cylinders and look for all 8 to be within +- 10% of each other.

Compression gauge fitting you need is just one that screws into the sparkplug terminal

Also inspect your rotor and cap for any missing points.

Also pull the valve cover on the side you think has the problem and check to make sure you didn't just toss a rocker which happens.
 
So if it was a rod or piston, would it still turn over (after multiple tries) and run like i described? Also, is there a specific size (like 5/8ths, ect) for our spark plug threads for the fitting?
 
BullittStangV8 said:
So if it was a rod or piston, would it still turn over (after multiple tries) and run like i described? Also, is there a specific size (like 5/8ths, ect) for our spark plug threads for the fitting?

If you ******* up a hard part like a rod or a piston you would know for sure.

If it was piston, the motor wouldn't run anymore by now.

It if was a rod, metal would have gotten to the pump by now and stopped pumping oil...and the motor would have seized (enless its just a bent rod)

When I bought my compression tester it came with all the fittings I needed...I honestly don't recall the thread size of a spark plug hole :shrug:

Things it could be from what you describe:
Bad wire
Bad plug
Bad Points
Non closing valve
Popped rocker
Bent Valve
Collapsed lifter

The list goes on.....

I am personally leaning towards a rocker fell off (simply because its happend to me in the past)...what RPM was it you were shifting at again? 5k? 6k? 6.5k? And what if any valve train upgrades have you down to support this RPM...you really haven't supplied too much info in your post about what has been done to the motor.....and the DETAILS about what EXACTLY you were doing when the failure occired
 
The shift was at about 4.5-5k. I dont rev it higher then that for fear of reving it higher then it can handle. The engine does have Magnum Roller Rocker Arms by Competition cams. What other type of info would be helpfull about the engine in order to help solve what went wrong? I aprreciate all the help your giving, as you already have been a great help in trying to figure out what went wrong. As for what exactly i was doing while i was driving? i shifted from first into 2nd at about 4.5-5k as i said. As i let out the clutch to get into 2nd, the engine died/stopped. I clutched in and rolled to a stop, and turned the key to off. I opened the hood to see if there was any visual clues as to what occured, and then tried to start the motor again. It eventually turned over, and i was able to limp home by keeping the rpms up in whatever gear i was in. If i let the rpms drop below 1500 rpms or so, the car would/will start to stall. It can hold a more elevated RPM like 2000 and above.
Mike
 
do you have an MSD 6A? i had one fail on me while going about 70mph...i almost pooped! i thought someone dropped a bucket of marbles down the carb. As the otheres mentioned i doubt it is a thrown rod or broken piston. probably something ignitin related, maybe something carb related? could have a stuck float or clogged fuel line.
 
timing chain may have jumped, check your timeing if it has mysterioulsy been retarded you need a new timing chain.

other than that just check your dist to make sure the mech advance didnt get stuck, check plugs, and check rockers, pushrods and compression(check compression last for if thats bad after everything else is checked then you have real problems). if you took out a piston or rod you wouldnt of made it home unless you burnt a hol in the piston
 
I vote for carb problem. If you can keep rpms above 1500-2000 without any hellish metal grinding, popping back firing, banging noises, it probably isn't an internal problem. My similar carb problem happened when I was just coasting and had same symptoms as yours, it wouldn't hold an idle without dying until I kept rpms above 1500.
 
I dont think its carb related, as a cylinder on the right bank seems to be down. So if it dropped a cylinder, that would make sense as to why it couldnt hold the idle.
Today im going to do the following:
Check plugs
Check wires
Check the rockers
Compression check
Ill see where im at after all that, and ill report back.
Mike
 
BullittStangV8 said:
Okay guys, im thinking my engine may have gone to the engine heaven, so heres where i need help. First the background. The engine is a 65 289, with stock heads, edelbrock rpm intake, a street deamon carb, a comp cam, and long tube headers. I was driving home and went to do i higher rpm 1-2 shift. Went to let the clutch out in 2nd, and then engine died. I pull over, stop the car and look under the hood. everything appears to be fine. Go to crank it, and it barely wants to start or hold an idle. I limp home, and just keep the rpms up above the stall point. (from idle (700 rpm) to around 1500 rpms. Above that it seems to not die out. Tonight i finally had time to start looking at the problem, and i had a friend turn it on, while i was behind the car. There is a definite miss on the right side bank. The left side i can feel and hear the 4 cylinders firing. (the pulses and audibly) Meanwhile the left side i can only make out 3. Seems like the right side has dropped a cylinder. Great..So now i have to try and hunt down the problem. Im fearing a broken rod, piston, or connection rod. Seems like worn rings wouldnt cause this much of a noticable problem. (i would suspect simply a loss in power for a worn ring) The car does not smoke from either tailpipe, and it has true dual exaust. So now im out to do a compression check to see if anyone of the cylinders isnt making compression.
If i have no compression, what are the possible broken components/reasons why it wont hold compression? It seems that if i find that compression is lost, im going to be tearing the engine down to find the problem. If the compression is fine, what would be other possible reasons for the cylinder dropping? Thanks for any help or feedback guys, i really dont want to loose this engine.
Mike
p.s what kind of fitting will i need to adapt to the compression gauge?

Once, I had a distributor freeze and then unfreeze a few degrees later. The result was what sounded like a miss (ignition was off), but I still had oil pressure. Another time, I had the roll pin that holds the cam driving distributor gear go so timing was way out. Yet another time the cam gear broke, breaking the gear on the end of the cam. The oil pump drive shaft also twisted and broke. If you pull the cap and turn it over does the rotor still turn? It is does, it is probably timing. It the rotor bumps up and down, pull the distributor and look down the hole and check the drive gear on the distributor. I've been running small block Ford's a long time; each of these things happened in different engines.

Another thing....if the heads are totally stock and you did not have the exhaust seats replaced with hardenend units, you could have had an exhaust seat retract (due to no-lead gas) and are therefore not getting compression. I've had that happen, too. It takes time but all of a sudden, compression drops dramatically and then goes away.
 
okay guys. i pulled the plugs and did the compression test today on the passenger side bank. heres the results i got, with one being the front cylinder, and 4 being the closes to the rear.
1) 120/130/150
2) 130/150/160
3)120/150/152
4)120/150/153

Heres how the plugs looked: plug in cylnder 1: dark tan/brown and oily looking.
2: light tan
3) whitish tan
4) Whitish tan w/ brown blemishes in two spots.
All of the tips were fine, and there were no cracks in the porcelain. The tip are all shaped properly, and the center electrodes are all whole/regular.

What does all this tell me? Since i have compression, wouldnt that mean that i havent broken a rod or piston? Also, wouldnt that mean the rings are okay? Finally, what should i check next?
Mike
p.s what trq rating should i reinstall my plugs at? and what should i apply to the threads prior to reinstalling the plugs?
thanks guys.
 
BullittStangV8 said:
okay guys. i pulled the plugs and did the compression test today on the passenger side bank. heres the results i got, with one being the front cylinder, and 4 being the closes to the rear.
1) 120/130/150
2) 130/150/160
3)120/150/152
4)120/150/153

Heres how the plugs looked: plug in cylnder 1: dark tan/brown and oily looking.
2: light tan
3) whitish tan
4) Whitish tan w/ brown blemishes in two spots.
All of the tips were fine, and there were no cracks in the porcelain. The tip are all shaped properly, and the center electrodes are all whole/regular.

What does all this tell me? Since i have compression, wouldnt that mean that i havent broken a rod or piston? Also, wouldnt that mean the rings are okay? Finally, what should i check next?
Mike
p.s what trq rating should i reinstall my plugs at? and what should i apply to the threads prior to reinstalling the plugs?
thanks guys.


Have you done what I first suggested? Put nothing on the plug threads.
 
well just when i thought things were looking up (meaning no major damage), i decided to check the other 4 cylinders for compression. The 2nd cylinder in on the drivers side head had no compression. The other 3 were fine. I pull the valve cover, crank it over, and all the rockers move, and everything is in order..A bent arm would give low compression, but everything moved properly and there still was no compression in the cylinder. I'm going to have to tear it down to see just what broke exactly. Im predicting a hole in the piston. A shattered piston would have seized the oil pump by now, and theres no loud "clanking" or grinding sounds.
I guess the tear down will be the final deciding action.
Thanks for all your help, you guys really were helpful in solving what went wrong.
Mike
btw, if it is serious enought ot have to rebuild,how much do rebuilds/forges generally cost? Im looking at forged internals, rods, and pistons, then finding a roots blower...:)