Plymouth 383ci Big Block question

[Johnny Turbo]

Hi all,

Unfortunately my 383ci has a blown head gasket. My question is, can the heads be removed for machining and reinstalled without having to pull out the distributor?

Looking at the engine, it looks like it's possible to pull the intake, valley pan, heads, front accessories etc.. without disturbing the distributor.

This is my 1st Mopar head job, I'm used to having to pull the distributor on SBC endings because the distributor goes through the intake.

It has a Tunnel Ram on it, incase that makes a difference.

Your thoughts?

 

[57fury440]

Yes.

 

[Johnny Turbo]

Yes.

Awesome, so the heads can be removed without messing with the distributor. THANKS!!

That makes the job easier.

 

[CBODY67]

ONLY need to mess with the distributor IF there are clearance issues. Same on LA motors, too. Advantage Chrysler!

 

[Johnny Turbo]

Ok thanks. From what I can see, the head will clear the distributor when I pull the heads.

Thanks!

 

[Lefty71]

How do you know the block doesnt need a cut??

 

[413]

Shall we discuss this possible blown head gasket? And save you some labor? It is uncommon to blow a gasket with 17 head bolts.

 

[Johnny Turbo]

How do you know the block doesnt need a cut??

I will have the heads milled and looked over. I don't know if the block needs milled. I do know If properly rebuilt heads and gaskets don't fix it, I'll just put a 440ci in it. I figured I would use it as a head gasket replacement lesson for my son. Just to get the car back on the road.

In my experience (several) with a blown head gasket, the block itself in most cases is ok. It didn't overheat. The car was sitting for YEARS, and we just got it running. We ran it for short periods of time, to try to heat cycle back to life, but it developed a small coolant leak into the oil. So now it turned into a head gasket replacement lesson I will walk him through.

If it works, awesome, if not... 440 time.

 

[mr gtx]

the block itself in most cases is ok.

very true

 

[Johnny Turbo]

Shall we discuss this possible blown head gasket? Amd save you some labor? It is uncommon to blow a gasket with 17 head bolts.

Sure we can. The oil is milky looking. When i got it ( several months ago) , the oil looked ok but dirty. Nothing out of the ordinary. We gave it some heat cycles over the 1st few days after gettingit running. The coolant looks good, the oil looked ok. I changed it and it's filter after I got it warmed up. Coolant still looked ok, but since I noticed the moisture on the dipstick i haven't let it run long enough to get the thermostat to open.

I have been doing some floor repairs, and occasionally I would let it run to help circulate it's fluids.

When i noticed it:

About two days ago I went to start it and it didn't have a very even start. Wouldn't crank smoothly. Seemed one of the holes would struggle. I checked the oil because it sounded like a possible hydro lock in one cylinder, and saw moisture in the oil on the dipstick.

I removed one of the exhaust manifolds to have it machined due to an exhaust leak. (The moisture was seen in the oil before removal of the manifold removal.... i think .
Either way the car was covered)

Oddly, 2 days later, I got the manifold back. Installed it, and fired it up quick to check if the exhaust leak was gone (it is). after I fired it up and it started smoothly and ran smoothly. No hydro lock struggle/gallop.

The car does sit outside, but it has a brand new "seal skin" brand car cover on it.

I do think I will change the oil this week if time permits. MAYBE somehow the cover leaked water into the carbs. I'll see if it happens again.

The carbs do stick through the hood as you can see in the picture. But it's been covered since I have owned it (several months) and never struggled to start with a hydro lock sound in 1 hole. And no, I have not had time to pull plugs yet to check for signs.

Since seeing grayish milky oil on the dipstick, I cover the carbs with plastic bags AND then cover it.

I will try to remember to post a picture of it tomorrow (it's after 10pm now)

In my experience milky oil is typically one of 2 things.

1. A blown head gasket.

2. Excessive moisture from not being driven in a damp environment.


What has me thinking head gasket is the struggle on one piston during cranking, that one time.

 

[volksworld]

the hydro lock could be fuel...a compression test with a pressure tester on radiator could show water leak, or running the engine and using one of the testers that use a dye to change color when it senses combustion gas in the radiator can pick up small leaks that other methods can't...tf you want to pull the heads anyway, have at it

 

[Johnny Turbo]

I thought it may be fuel too, but the oil on the dipstick didn't smell like fuel.

As I mentioned earlier, I have not had time to pull the plugs and really look into it.

I was just asking for my knowledge if the heads can be pulled without pulling the distributor, IF it came down to a blown head gasket...

lol I was glad to hear the heads can come off without pulling the distributor. NOT because it's hard, but i was already looking at aluminum heads and cams. If the distributor had to come out I could easier justify to myself, heads and a cam swap. I am trying to keep this built "cheap" and fun for my 10 yo son and I. I have a hard time pulling off stock stuff and replacing with stock. It's been a struggle of mine for decades lol.

 

[Johnny Turbo]

A look at the oil dipstick as promised.

Note: The oil brand is PennGrade so it comes a bit darker than most brands. Also the oil has MAYBE 2 hours total of run time on it.

 

[Sixpactogo]

My question is "Why the concern on pulling the distributor?" None more simpler than a big block Mopar to re-orient.

 

[413]

Problem #3 for milky oil.

Cylinder head ported too much and it's cracked, letting. coolant in the oil.

Whatever it is sounds like you have to find out why it's doing that.

Just know some aluminum heads won't clear a stock distributor on a BB mopar. They sell tall distributors now for this reason.

 

[Johnny Turbo]

Problem #3 for milky oil.

Cylinder head ported too much and it's cracked, letting. coolant in the oil.

Whatever it is sounds like you have to find out why it's doing that.

Just know some aluminum heads won't clear a stock distributor on a BB mopar. They sell tall distributors now for this reason.

Another good thought. I believe these heads are stock. They are definitely cast iron, and when i put the HP manifolds on it, i didn't see any visible head work. The rockers, springs etc. Look to be stock/original. The car is a true 85,000 mile car. So im guessing everything except the tunnel ram is original.

(Yes it has a tunnel ram intake, but i think the previous own did that for the looks.)

I suppose I'll try changing the oil and filter. Then run it again, incase some how water got in it when the manifolds were off getting machined. I'll also use a bore scope.

And go from there.

Thanks again folks

 

[413]

Yes oil change is cheaper and easier than pulling heads.

 

[Johnny Turbo]

Yes oil change is cheaper and easier than pulling heads.

True story

 

[Lefty71]

I would certainly change the oil and give it some serious run time if you dont see anything doing damage before pulling anything apart.

 

[Johnny Turbo]

I would certainly change the oil and give it some serious run time if you dont see anything doing damage before pulling anything apart.

Sounds like a plan. I rebuilt one of its Carborators today. I'll do the other this week, then drain the oil and give her a good run.

I couldn't really drive it because both carb's squirter diagrams were/are not functioning properly, so it would go lean and die out anytime I tried to drive it.

One is now fixed, like I mentioned I'll get the 2nd one later this week.