Hey Guys,

I am diagnosing some engine problems on my rebuilt 440. It is a little hard to start, but once it does, it idles decent. Take it out for a spin, and it runs like a DOG, and runs rough. I am going to do a leakdown test on it. Thought it could be a head gasket, since it was getting hot when I drove, but no oil/coolant mixing. However, it did look like there was some metal particles in the coolant? Hopefully not a bad water pump.

I thought my timing chain sprockets could be off a tooth, or the distributor gear being off a tooth. When I rebuilt, I double checked the alignment of the sprockets and looked to align right? I know when the distributor gear is dropped in, the slot is supposed to align parallel to the camshaft, correct? Well, every time I tried turning the distributor gear in, no matter which way I tried, the slot would never line up exactly parallel with the camshaft at #1, TDC. Could this be a suspect of the timing sprockets being off a tooth? I know it shouldn't matter as long as you align your distibutor to fire at #1 TDC. Just wondering if this could be a suspect of a timing chain off one tooth?

 

Fastdakota84,
With the rebuild, did you use a new timing chain set?Did you line up the timing marks on the sprockets? Was there any slack in the chain? The slot in the oil pump drive shaft can line up any where. Get your timing light out and check your timing. Also make sure the advance in the distributor is free and not stuck. john

 

On the rebuild, I did use a new timing chain. Yes I lined up the marks on the sprockets, but I could of been a tooth off? I used what straight edge I had available to double check the alignment of the dots. There shouldn't of been any slack since it was a new timing set, but I don't remember, it was awhile back. I've adjusted my timing, and doesn't seem to be an issue, not jumping around. I just runs rough when accelerating, sluggish acceleration, and slower then I thought it would.

I know the slot can be anywhere since it depends on your timing. I was just referencing if the slot was not parallel to the cam, that would tell me if I was a tooth off.

 

Okay, What exactly was done to the motor for the rebuild? New cam,pistons? Any work done to the heads? Machine work on the block? Did you check for any vacuum leaks?

 

Sorry, I've been out of town. On the rebuild, yes, new cam, new pistons, factory heads machined for straightness with valve bores opened up to next bigger size for bigger valves. Block bored .030 over, the usual checks and cleaning from the machine shop for a engine rebuild using factory block and heads. All new parts except, block, heads, crank, and rods. I did check for vacuum leaks and didn't find any. Once I do a leak down test, hopefully that'll let me know.

 

how big of a carb did you put on

 

I have a 770 Holley Street Avenger on it.

Also, on the rings, they are moly steel: Sealed Power ZE424K30

I haven't had a chance to do a full compression test, but on a quick test on the #1 cylinder it seemed low, engine cold, ~133 psi. I should have ~9.5:1 compression which I think would have a higher cylinder pressure than that. Also I am getting blow by it seems; oil dipstick pushing out, little oil leaks. How long do you think these rings should take to seat? I didn't think they should take long. I haven't really got a chance to take it out and break in the engine since it ran kind of rough. It's mostly seen idleing in the garage trying to tune.

 

With that new cam,what kind was it? Roller,flat hydraulic,solid lifter? On the initial start,did you spin the oil pump to prelube the block?

 

What kind of crankcase ventilation do you have? If you are pushing the dipstick out, you don't have enough ventilation (ie bad pcv) or maybe a cracked ring or two.

 

I have a hughes engines 2832 Flat Hydraulic cam. I did prime the oil pump before start up. I thought maybe some lobes went flat since I was cranking a little and I didn't have spark, but it doesn't look like it is, of course I haven't looked at the other valve cover and crank over to see the lift. Hughes said I should have around 10-12 in vacuum and I'm only getting around 5 in vacuum also.

I have a PCV from valve cover to carb and oil breather on other cover. The PCV is good, its new, rattles when you shake it.

How would I know for sure if I would have a bad or craked ring or if the rings just haven't set yet?

 

Fastdakota84, Sorry for the dumb questions,I don't know your skill level but you seem very competent. That Hughes cam is a good choice,did you get adjustable rockers? For the rings,moly rings usually seat pretty quick,did you check the ring gaps? And finally,did you do a leak down test yet?

Too bad you are so far away,it's hard to figure out a problem over the net.

 

John Van,

No biggy. I appreciate the help! Yea, I thought the Hughes cam would be a good one. I do have adjustable rockers. I thought moly rings set fairley quickly. I did check the gaps before installing them and file them to the correct specs. I've been so busy latley I haven't had a chance to fully complete the leak down test. I did the #1 and #3 cylinder last night but it got late. I'll finish the rest hopefully this weekend and get the #'s posted.

So Far:

#1 cylinder: 5% leakage
#3 cylinder: 9% leakage

I know these are still pretty good and in the range for a leakdown. This is with the engine cold since I was having trouble starting it, plus being late, and the truck is LOUD.

The only thing that makes me wonder about it being the rings is because I can hear and FEEL air coming out of the oil breather hole in valve cover. But I know if it's leaking it's got to go somewhere. Is this sign so far of being a ring problem?

 

UPDATE:

Ok, I did a leakdown test and a compression test on all cylinders today. The test was done engine cold since I had trouble starting it up. I am a little confused between my leakdown and compression test results. I am getting good readings on my leakdown test and low #'s on my compression test. Maybe someone could point me in the right direction. I know a stock 440 should have around 130-165 psi compression. I have stock "452" heads (81.5 cc), and am using KB hypereutectic flat top pistons. With that set up, I was expecting around 9:1 to 9.5:1 compression, with that, I thought the pressure would be around 175 psi, but it's not that at all.

Here are the results:

Leakdown Test:

#1: 5% leakage #2: 5% leakage
#3: 5% leakage #4: 5% leakage
#5: 8% leakage #6: 4% leakage
#7: 5% leakage #8: 5% leakage

All of the leakage came from the oil breather or PCV. I could feel and hear air. But I know the air has to go somewhere.

Compression Test:

#1: 140psi (dry); 140psi (wet) #2: 150psi (dry); 152psi (wet)
#3: 120psi (dry); 120psi (wet) #4: 112psi (dry); 115psi (wet)
#5: 104psi (dry); 106psi (wet) #6: 130psi (dry); 133psi (wet)
#7: 125psi (dry); 130psi (wet) #8: 131psi (dry); 133psi (wet)

These #'s are all over the place. So I am just not sure if the rings haven't seated yet, since I haven't had a chance to drive it much, or if the rings are bad??? But, they are not around 175psi either, they are pretty low?

As you can see also, how this doesn't add up to my leakdown #'s either? Almost like the pistons aren't making the higher compression?

Thoughts anyone? I'm a little confused?

 

Fastdak, The rings are fine;no big increase between dry-wet numbers.I would double check the preloads on the lifters and also check on the cam timing. I'm confused too!!

 

Well, I figured out the problem, looked at a week ago. I double checked my cam timing, and sure enough, I am off 8°, telling me I am one tooth off in timing. I took off the cover, and yep, one tooth off. So, once I get that lined up, hopefully all should be good, a run alot better! Thanks for the help. I'll let you know the results.

 

Hey, at least you found something wrong! I hope that's it,I got my fingers crossed!

 

Hi,

I am curious to know if you still have the blow by issue. With your set up--and a KB piston that comes near the top all your cylinders should hit 150lbs. That is approximately 9.5 ratio. 452's are closer to 89-91 cc's unles you have had them milled .050-.060. Did you lightly tap the pistons into the holes? Did any hang up with force to knock them in? Any force other tahn a little tap with rubber end of hammer and you can snap a ring. But you are all over the board.

I question your heads if they are sealing. Even one tooth off, your cylinders should still pull the same pressure(consistency only). If you had fresh bores and rings, They seat pretty quick. You wont pick up 40lbs cylinder pressure. What were your end gaps on the top ring? What you are running I think you can get them down .015--.020...I like tighter gaps on your basic moly rings. I ran mine .015 on 6 pack pistons with excellent seal. You might be leaking in the heads.

Did you check the heads before installation? ie simple test is pour water down the ports and check valves to see if any comes out past the valves on the seat. They shouldnt leak at all. no water drops, none, for a good seal. Its rings, cylinder or head. Your dipstick shouldnt move at all. I run 210 lbs on my 440 6 pack motor--and no blowby, ever...however I rebuilt a 340 with bores just a little too big--and a lot of blowby............
but your new non filed rings will tell the story of the accuracy of your bores.

I would start with the heads--pull them and check..look for bent pushrods....cam lobes...If not them, pull the motor--sooner than later--and check gaps and for broken rings. Otherwise, everytime you start it and drive it--it will eat you thinking about it-- you are going to be concerned with it not running as well as it could and should--I have been there, done that. you can have your motor out in 2-3 hours....

Make sure the cam lobes are not ground down or some of them...when the heads are off.....

 

I'm happy you found this, but here's a few rumblings from the darn near senile.

First, I would learn to "degree" a cam as per the recommendation of the cam grinder. Don't trust factory timing marks.

Second, you mentioned the drive gear and distributor. This has nothing to do with the problem. You can set the timing WITH A LIGHT and it MATTERS NOT where the gear and distributor is. That is to say, on initial fire-up, you can literally drop the drive gear and distributor in "any old way" and simply plug the no1 wire in where ever the rotor points with the timing marks on no1 to fire, and IT WILL RUN just fine.

(On my first car, a 57 Chiv 265, I new nothing of the "right" way to drop in a dist. I had one service station jock tell me my car had to be out of time!!! because the distributor was wrong)

To check factory marks: Do this with a "positive stop" either before or after the heads are on. You can easily make a stop with a scrap of flat steel or even angle iron--just bolt a piece across a cylinder with two head bolt holes, with a bolt in the middle poking down. If the heads are on, use a spark plug stop:

http://www.purgeraptor1.btinternet.c...oslockstop.jpg


Using either stop, rotate the engine 'til it stops, and make a mark on the damper under TDC on the tab. Do the same oppposite rotation, and the true TDC will be halfway in between the two marks you've made. If the original marks are correct, that is where it will be.

The only reason on MOST engines that the manual specifies a specific distributor position is:

So the assembly like folks can wrench, repeat

So tuneup mechanics "see" what they expect

So the plug wires "lay" correctly

So the vacuum advance is somewhere "handy."

On older GM cars, of course, proper installation also put the adjustment window so you could maybe reach it

There ARE engines that "matter" The V6 series of the 60's/ 80's (remember even, odd fire?) These had distributor lobes with alternating pairs of cylinders that fired closer (in degrees) the next pair further. You could SEE this by examining the dist. cap and rubbing block.

CAM DRIVES. I don't remember if Mopar did this, but some manufacturers (Ford 460) had "smog" advance/ retard BUILT INTO the cam drive. This means that when the cam is "on the dots" it's still "really" out of time so far as performance goes.


You'll hear and read all sorts of conflicts on the www about "cam centerlines" and so on, but I still maintain that the CAM MANUFACTURER is the guy to refer to as a starting point for a cam install.

Here's one last thought: On many U.S. V8's, when the cam is "on the dots" as pictured in most service manuals, that IS NOT "no1 ready to fire" but is in fact on no6. I lost a bet about this one time, look next time you run across a V8 on display in a parts store. This is only important on such engines as Mopar BB V8's, because it's possible to drop in the drive gear and dist. after you've replaced a timing chain or cam, without rotating the engine. You'll find that it's the ol' "180* out" routine, and scratch yer head because it's flaming out the carb throat.

Been a long time since I've "been into" a 440. I've been beaten down to a 273!!

 

Hey guys,

It's been awhile since I've been on here, staying pretty busy. But I thought I'd let you know what happened with this situation. I degreed in my cam and the timing set was way off from the marks. I had to install a degree bushing also. But I got it degreed correctly and it runs alot better! It'll really haul now! But... I'm still having some issues with blow by. I don't kow if that will just go away over time, but I'm gonna double check some of my PCV issues. My oil dipstick will push out a bit after I drive, and there are some small oil leaks on the ground, don't know from what though. I am around 8 inches of vacuum with this cam. Could it be there is not enough vacuum for the PCV to open? Also, oil pressure is high at around 80 psi. I heard that will go down after awhile since there are tight tolerances on the bearings. Any ideas on the blow by would help.

Thanks!