440 engine problems...need help

[moparfanUSA]

I have a friend that just had his 69 440hp rebuilt to stock specs, but bored .030 over.
1st the engine runs hot, on the highway about 215, on side streets 200, we have put 3 different thermostats in 160, 180, and 195, all with about the same results, he went from a 2 row (from the factory) to a 3 row (using the old rad that came with the car from the factory...and yes it has been folw tested...33GPM)
2nd before he had the engine done he could lite up the tires, now the tires spin for about 2 sec, it just seems like it does not have the power it once did.

Seems to be burning oil, so we did a compression test with the following results.
lowest is 140 and highest is 145. The car was warm when it was done. Took out the spark plugs and the number 6 plug was mostly black with oil build up, so we think maybe we have a broken oil ring, but that would not give us that much lessm horsepower. The other plugs look good, maybe number 4 is a little off. We have replaced the valley pan twice after changing out the cam, that did not let the car idle well, new cam has it running smooth at idle.
We have about 15deg of timing at idle and as near as we can tell since we do not have a timing tape on the damper, about 45deg at about 2500rpm.
He is using a Mopar distributor (elect. ING...with the orange box). Car has A/C.
We have tried about 6-7 different carbs, with 750 being the biggest and finally putting a 650 on it.

Why cannot we get the power it once had before? They are stock heads, and they have been done also. I really thought that the compression test was going to give us the answer, but it looks good.
We are stumped. Anyone have any suggestions?

 

[74Satellite]

first thing that pops to mind...is a poor rebuild job. I had an engine rebuilt by "a friend" and it ran like total garbage, idled smooth and sounded great until a load was put on it and it had no umph at all... tore it apart myself and the tard left the plastigage in the bottom end. Spun all kinds of bearings. Sold the car....

 

[green1]

what cam specs?. what advertised compression? What is idle vacuum? Guess 45 degrees?

 

[scotts74birds]

I'm saying this so you dont discount the obvious, but it still may not apply to you. I am curently rebuilding, and replacing 2.7 motors in late model chryslers. I am making some good money doing this. I know their problems, and I know the fixes. One of the big ones is that the t-stat that you buy is ****!!!! We used to trust Standt, and Bosch, but that is no longer true! I bought aftermarket stats, and then compared them to stats that I bought at the Dealer. The factory stats were about 3/4 " longer [allowing greater flow], and about twice the weight!

 

[Cranky]

A 69 440hp should have a higher cylinder psi than 140. Stock pistons in them were up close to the deck. I don't remember the exact figure but I'm thinking they were no more than .050 in the hole and replacement pistons are usually .100 down! Most stock replacement pistons are sold by an 'advertised' compression but that's the max expected if everything possible is done to achieve that compression and if not done, you end up with a lower figure. Always buy pistons by the compression height and not by the advertised figure....for example, a 6 pack piston has a compression height of 2.062 which is in most cases about .020 in the hole (blocks can vary). Also, what cam is in it and how was it installed? If it was installed using the dot method, then you have no idea if it's a few degrees off. If it's retarded 4 degrees or more, that could be why it doesn't have much pep. The tolerances in the machining of the cam plus the sprockets could all add up against you and then you have the instances where the sprockets or cam are machined totally wrong and the car doesn't run at all and bends valves. Yes it's happened!

 

[Meep-Meep]

A broken oil ring is very unlikely since what you seem to get these days are the three piece type. A broken compression ring is very possible but looking at your compression variance I'd say no. I'd be concerned about the oil fouling for sure but it may be coming from the guides. 140 PSI is not great so you may have a component mismatch problem. 45 deg of total advance better be with the vac advance hooked up. You should have 36-38 in the dizzy and another 8 deg or so in the vac advance. 15 at idle is OK. How about a dynamic compression test? Pull a plug wire out of the cap one at a time while the engine is running. You should have an equal RPM drop on every cylinder. If no change in RPM then that cyl/cyls is not contributing to the output.

 

[moparfanUSA]

I have asked some people and most think it is a valve giude seal, but I have taken the plug out and found out that the end has been closed shut also, this has happened on 2 plugs in the same cyl. does not look like the the piston hit it, but looks like it might be detonation, both #4 & 6 cyl, are running very hot. We poured water on the intake manifold on the other side the water just warmed up, but on the 4&6 side the water started boiling right away. I have a 272-284 cam in it, so I do not think that is the problem. I drove it to Carlise this weekend...3 hours and once I got there I had to change the plug as it was fouled. The car ran at 210-215 deg the whole way out. Once we got there took out the thermostat and did not put one back in, it then ran at about 185-190 much better, so since the engine has been running so hot, I might have burnt the valve seals. I plan on taking the head off soon. BTW...if 140-145psi is not good for a 440, then what should it be?

 

[moparfanUSA]

BTW...the 1969 service manual, says the compression pressure should be 130-165psi

 

[ga66mopar]

Also, what cam is in it and how was it installed? If it was installed using the dot method, then you have no idea if it's a few degrees off. If it's retarded 4 degrees or more, that could be why it doesn't have much pep. The tolerances in the machining of the cam plus the sprockets could all add up against you and then you have the instances where the sprockets or cam are machined totally wrong and the car doesn't run at all and bends valves. Yes it's happened!

Like Cranky said if the cam wasn't degreed in you have no idea if your cam is retared or advanced. I installed a comp cam recently and some other brand timing chain and it was 3 degrees retarded with the dots lined up.

 

[moparfanUSA]

The guy that put the cam in used a cam degree wheel and set it for TDC.
I was there and saw it.

 

[moparfanUSA]

Well, we are going to pull the engine on Sat. so I will find out then.

 

[Cranky]

BTW...the 1969 service manual, says the compression pressure should be 130-165psi

Imo, the service manual is pretty broad and a good running 440 won't check out at 130. I've never had a reading that low on a 440 that was still in good condition.....not a 69 anyways.

 

[696pack]

Imo, the service manual is pretty broad and a good running 440 won't check out at 130. I've never had a reading that low on a 440 that was still in good condition.....not a 69 anyways.

Yes, as were the factory built engines that were all over the place regarding how far down in the hole the pistons were that contributed to the spotty compression. You and I both know that a WELL BUILT after market rebuild will by much closer and much higher than what the service manual states.

Reading between the lines I think that the OP has little mechanical knowledge from his comments and I have been keeping my mouth shut about all of this as some of the comments after some good info given to him seems to be challenged. Not throwing stones here, just an observation.

He is going to disassemble and HOPEFULLY he will have a professional examine what he has.

 

[moparfanUSA]

Just to be clear. I had a professional shop (that is all he does...nothing else) rebuild it for me. he has done alot of engines for my friends over the years, problem surfaced that he has only done 1 mopar before. He builds race motors for Nascar (not cup) and for short tracks, but they are all Chevys or Fords. I'm pulling the engine and bringing it back to him...I'm not guessing, nor was I going to try and fix it myself.

 

[wlo48]

I didn't read anything about exhaust or exhaut manifolds. The factory manifolds have the heatriser in the passenger side. If it froze shut during rebuilding than all the exhaust is being forced under the carb and out the driver side and than back to the passenger side if it is a single exhaust or it goes down the driver side duals. This will cause the manifold to run HOT, could cook the valve guide seals, and if let alone could cook the temper out of the rings in the two middle cylinders, but it has to get REAL hot to do this. With it having NO power, check there first, nothing to loose. All entries has mentioned the timing, that is important. No mention of the coil or spark plug wires. Also the ignition resistor on the firewall could be cutting voltage too much and giving poor spark. Running hot sounds like the timing is too far retarded, but that has been checked also. Please don't run it without the themostat. The themostat is a valve that controls water flow through the back part of the block. Without it to control the flow the back part of the block gets hot and the front gets cooled because the water will take the path of "least resistance" and not flow to the rear part of the block. If you want to run the coldest themostat, fine, but at least run one. You said you were pulling the block, check the cross over port under the carb. If the heat riser is stuck shut like I said at the first, and the cross over port is closed by carbon, gasket, or what ever, the motor will run very bad because there is no where for the exhaust to go from the passenger side. This is just a thought here, but if the motor is coming out, well now is the time to check it.
These are just thoughts from my many 440 days.