230 ci Head on 1054 Dodge Coronet Suburban

[Rood]

I am new to the sight so forgive me if this is the wrong place to ask these questions. I started working on a 1954 Dodge Coronet Suburban that I have had for 22 years. I bought it from a used car dealership. It ran ok on the short test drive but a major overheating problem and charging issue on the way home. Well, life happened and I never had the time or money to make the repairs. So it just sat there.

 

So after 22 years I started working on it and got it running great accept for the overheating issue. Had exhaust leaking into the radiator so I figured the head gasket was shot. I started tearing it down and unfortunately broke two head bolts off. I don't think the head had ever been off. Still trying to get them out. The head has 003 to 004 thousands gap in a few places and I am not sure if that is ok or not. I read in one of the other forums that you could get away with 006. but I don't know if that is true.

 

When I was cleaning all the carbon from the head I noticed a small hole in #6. I started picking at it and it got a little bigger. It looks like someone drilled a hole and then filled it with something. I will attach pictures. I am not trying to do a proper rebuild on the engine yet, I just want to get it all back together to see if it will stop overheating and run it for a while. I got the water distribution tube out, that was fun. I had to drill out two holes in the block that were totally plugged where the water circulated. Most of the holes in the head were plugged as well and all kinds of chunks and rust.

 

I flushed the engine and got a lot of rust and chunks out as well. So the questions at this point are the allowed tolerances on the head for flatness, what is the hole in the head and can I fill it with JB Weld? Any help would be greatly appreciated.

 

Thanks,

[Dodgeb4ya]

That's a factory timing gauge hole.

See the removable  hex plug above it.

Edited October 16, 2023 by Dodgeb4ya
Spell check

[Rood]

Thanks for the response, but I don't see the removeable hex plug. All I see is the hole above where the spark plug goes.

[Rood]

I understand now, the plug is on the top side of the head. I see it. Sorry about that

 

Thanks

[Jerry Roberts]

That hole gets plugged up with carbon . Since you have the head off , call a local machine shop and ask what the charge would be to mill the head flat . 

[Veemoney]

If you do choose to mill the head flat, consider taking some additional material off to boost the compression ratio. It really wakes up these low compression motors. I included a link to what I consider a conservative head milling chart located on this site. On my truck I removed .070-.080" with no issues and still runs cool. 

 

[Sniper]

14 hours ago, Rood said:

The head has 003 to 004 thousands gap in a few places and I am not sure if that is ok or not. I read in one of the other forums that you could get away with 006. but I don't know if that is true.

 

That depends on a few things, type of head gasket, which way you are measuring the head, type of head material, etc.

 

Copper head gaskets are less forgiving of surface issues than a composite, both are available for the flathead.

 

Max variance along the LENGTH of the head would be .006" and 0.003" ACROSS the head, for composite, less for copper.  This is for a cast iron head, less for aluminum.

 

As suggested, take the head to a machine shop and get it resurfaced, won't get easier than now, or cheaper.

Edited October 16, 2023 by Sniper

[Rood]

I appreciate everyone's response. Sniper, I'm using Fel-pro 7564c head gasket, metal on one side and a blue gasket material on the other. I called a machine shop and he said he could resurface it for $50.00 so no reason not to go ahead and do it now while its apart. It is a cast iron head. I did not think it would be that reasonably priced. That is the cost of another head gasket if it failed by not having it machined. 

 

Veemoney, I am going to ask the machinist when I get there if he can take off that much. I looked at the chart you provided and it suggests .050. If the compression is raised that much are there any problems that could arise by adding more compression? No idea what the mileage is. I don't think that this engine has ever been apart. I say that because the head gasket that was in there was all metal and carbon all over it and was burnt all over. The oil filter canister had almost 3/4" of grey putty in it which I assume is from the old leaded gas back in the day along with never being cleaned. It took a long time to get that cleaned out. I still need to drop the oil pan because I am pretty sure it is caked in there as well.

 

When I got it running after sitting for over 22 years, it ran pretty good. It smoked a little at first, burning off all the oil and wd-40  I dumped in the cylinders before I turned the engine over. It ran for about 5 minutes and the smoke cleared right up. I need a new water distribution tube, head bolts or studs and I think I am going to put it back together after I get the head back from the machine shop. Is there any advantage on these old engines to use studs rather that head bolts? I found the head bolts but no studs yet.

 

Thanks again for all the great advice.

 

 

[Veemoney]

Rood,

Based on your start-up information after sitting for 22 years it quit smoking after 5 minutes running and ran well. No pieces of piston land, rings or cylinder condition were mentioned so assuming all this is correct you should be good. The over-heating may resolve with the new water distribution tube and flushing you did. 

 

Taking .050" off the head should not cause any issues on your motor that are not currently present. That amount according to the chart would give you 7.7 ratio which helps but it is still low compression.

Some other things you may look at closely if you have not already:

1. Check the top of the pistons to see if they have any numbers like for example .010" which would identify the pistons are oversized by .010" and possibly the motor was rebuilt at some point.
2. Engines were swapped out often so if you haven't already checked the number on the driver's side of the engine block to confirm it matches up with your title or production year that helps for future reference. Some cars were titled by VIN and some by engine number.
3. Head casting number is good to confirm since compression increases were done so later heads typically had higher compression and many were swapped as a performance upgrade.  

 

 

[Rood]

Veemoney, 

 

I had not even cleaned the top of the pistons yet. They were caked with carbon. I got home and cleaned a couple. They are stamped 060 so it has been bored before. The cylinder walls look great, the top of piston #6 has been beat to heck but must have been from a previous issue and they didn’t change the pistons. I was really surprised how good a shape the cylinders were in. So maybe it was bored not to long before I bought it. Who knows. 
 

I didn’t see any chunks of anything on top of pistons so hopefully all the damage on top of pistons was before the bore. Pics below. I will include pics of head and block as well with casting numbers. If someone can identify the year that would be great or tell me where to go to look it up. Sure would be a nice surprise if I had a a later head with a block bored 060 that might make a few more hp’s. 
 

 

[DJK]

17 hours ago, Rood said:

I appreciate everyone's response. Sniper, I'm using Fel-pro 7564c head gasket, metal on one side and a blue gasket material on the other. I called a machine shop and he said he could resurface it for $50.00 so no reason not to go ahead and do it now while its apart. It is a cast iron head. I did not think it would be that reasonably priced. That is the cost of another head gasket if it failed by not having it machined. 

 

Veemoney, I am going to ask the machinist when I get there if he can take off that much. I looked at the chart you provided and it suggests .050. If the compression is raised that much are there any problems that could arise by adding more compression? No idea what the mileage is. I don't think that this engine has ever been apart. I say that because the head gasket that was in there was all metal and carbon all over it and was burnt all over. The oil filter canister had almost 3/4" of grey putty in it which I assume is from the old leaded gas back in the day along with never being cleaned. It took a long time to get that cleaned out. I still need to drop the oil pan because I am pretty sure it is caked in there as well.

 

When I got it running after sitting for over 22 years, it ran pretty good. It smoked a little at first, burning off all the oil and wd-40  I dumped in the cylinders before I turned the engine over. It ran for about 5 minutes and the smoke cleared right up. I need a new water distribution tube, head bolts or studs and I think I am going to put it back together after I get the head back from the machine shop. Is there any advantage on these old engines to use studs rather that head bolts? I found the head bolts but no studs yet.

 

Thanks again for all the great advice.

 

 

Along with the oil pan, it is a good idea to remove the side covers to clean out the residue. I use Caterpillar #1D4556 for head bolts except the two with threaded holes in the top.

[Rood]

Thanks for the advice. I’ll do that. 

[Veemoney]

Here is a thread talking about the same part number as yours. I couldn't make out the block numbers so second link is to a site with numbers for L6 blocks to confirm your engine. Hope this helps

 

Flathead Engine Numbers: 1958-1968 (t137.com)

[Jerry Roberts]

18 hours ago, Rood said:

They are stamped 060 so it has been bored before. 

Since your engine has been rebuilt , at least once , your head might also has been previously milled . That means that you need to be careful about not removing too much material when you have the head milled . 

[Rood]

Thanks Jerry, I was going to drop off the head today but didn’t make it. I wanted to ask him if he knew the thickness of the head originally before taking off any more material than needed. I had asked another guy if he knew and he was going to talk to someone he thought might know. 

[Rood]

The engine number is M230*T3990T* so with the the chart on T37.com, it says it’s a 1959 block. That supports the later head that you sent the information on Veemoney. That’s good news to me. So on a bone stock 1959 it has 8:1 compression and 135hp. The block has been bored 060 and hopefully will be able to shave the heads another 050 unless it has already had some taken off. 
 

Will try and drop off the head later this week. When I get it back I’ll start putting it back together. I will update when it’s done. Thanks to everyone on this sight that took the time to help me out and share some of their knowledge. I really appreciate it.