4Msfam
4Msfam New Reader
11/29/13 11:49 p.m.

I've slowly been trying to get my daughter's '55 Dodge C3 truck running. The last step needed mechanically was finding and installing a new radiator. Sadly, my triumph of adapting a Rodeo radiator to the Poly block V8 was met with coolant bubbling out from just above and to the side of the number 1 spark plug. It appears to be coming from the side of a bolt securing the head by spark plug number 1 Is this a cracked head? Oil is clean. Fires well. Coolant comes out faster with increased revs.

Ideas?

Vigo
Vigo UberDork
11/30/13 12:04 a.m.

I cant picture the area you're speaking of but if it is coming from a bolt hole i would at least take that bolt out and silicone or thread tape the threads and see what happens.

oldopelguy
oldopelguy Dork
11/30/13 12:18 a.m.

Some of the poly head bolts go into the water jacket and need sealant or locktite on them to prevent leaks.

44Dwarf
44Dwarf SuperDork
11/30/13 8:34 a.m.

Darn to bad your on the other side... I've got a NOS mopar rebuilt 318 poly i've been wanting to get rid of.

Rob_Mopar
Rob_Mopar SuperDork
11/30/13 8:58 a.m.

Are you talking about one of the lower row of bolts in this photo?

4Msfam
4Msfam New Reader
11/30/13 9:25 a.m.

Yes Rob! In the pic, it would be number 6, but on the driver's side block. Not sure if it matters or not, but it's a 273 EARLY poly block (1955). I didn't build the engine (and I'm finding a LOT of PO shortcuts on this thing).. there's plain grade 8 bolts assembling the head and intake manifold. Do I need special bolts too?

44 Dwarf... I'd love to hear more about your 318... I love the shape and sound of these things!

When we first got the truck, we swapped out the carb, and were pretty excited just to hear it start! I think I've got it running a bit better now, now that I figured out the carb and choke.

A very excited father / daughter get the truck started

Rob_Mopar
Rob_Mopar SuperDork
11/30/13 10:21 a.m.

Nice truck. And very cool that your daughter took the keys.

That's probably a 270 Poly in there. It's been a long time since I looked inside a Poly, but that bolt should be into the coolant passage. Do like Vigo & Old Opel Guy suggested. Pull the bolt and put some sealant on the threads. Drain the coolant down first.

The grade 8 bolt is probably fine. I don't remember them requiring any special bolts there, but I would have to go do some digging to be certain.

Kenny_McCormic
Kenny_McCormic UltraDork
11/30/13 1:17 p.m.

Could have blown out the gasket from the cylinder to that bolt?

4Msfam
4Msfam New Reader
11/30/13 2:14 p.m.

Thanks for the suggestions guys, I'll try pulling the bolt and sticking some RTV on the threads. I don't think it's a gasket, as there's nothing leaking from the head/block sealing area externally. It does seem like it's traveling up the bolt hole and coming out just under the bolt head. I'll report back later.

4Msfam
4Msfam New Reader
12/2/13 6:20 p.m.

Well. Looks like I have more work to do. Sealant stopped that leak, but now I notice it looks like I need to seal the exhaust manifold bolts too. Gotta love PO's and their work. On the plus side, I'm going to learn every bolt on this truck by the time we're done! Thanks for the help guys!

44Dwarf
44Dwarf SuperDork
12/2/13 7:44 p.m.

You don't want silicone you want thread sealant / pipe dope. You might as well do them all one at a time and yes you'll need to do the exhust stud holes aswell.

My motor was NIB but some guy bought the F'ing box for a display..... I was told it was a 340...showed up to find a poly and bought it anyway. Factory long block no distrib, no valve cover gaskets, no freeze plugs, no water pump. About 14 years ago i was going to put it in a power waggon and bought all the stuff it needed to swap it in but never got around to it....they gave away the truck.... Let see....i was still living at Mom and Dads when i bought it....so i've had it over 20 years. I tried to sell it then in Hemmings and some guy wanted the box (wooden crate) with the paper work but didn't want to pay for shipping the motor.. You can read 0.020 on the tops of the pistons

4Msfam
4Msfam New Reader
12/2/13 9:48 p.m.

Sounds like a cool engine! Like I said, I do like the shape of the valve covers. The '55 was to be a father / daughter project. She and I did learn a lot (previous to this, my most ambitious project was swapping in a 350 into the family Astro. That was a bunch of fun!), we swapped the carb, put a new disk brake setup on the front beam axle, swapped out the points for a Pertronix setup. Figuring out the master cylinder replacement took a while. Now she's off in college, and I've got a project on my hands.

I did get some Permatex thread sealant. And do plan to go through each bolt and reseal them. There's so many… "hmmm… what to do.." with this old engine though, The water pumps are no longer available (that I've found). To swap in a Chevy BB pump requires a new timing cover, which would mean the cam needs to be shortened, which means I need to get a new engine mount system as the new one doesn't work with my current front mount setup. Which means the fuel pump needs to be swapped to an electrical setup…. blah blah. My goal right now is just to get it running enough to use on a occasional basis.

I've half thought about swapping the body onto a S10 or Dakota… I'd really like to use this for a fun AX rig, maybe a rallyX or two for kicks. Decisions / decisions.

Rob_Mopar
Rob_Mopar SuperDork
12/3/13 8:52 a.m.

Just an FYI, not all of the Poly motors use the same block to bellhousing bolt pattern. The later ones use the Mopar small block pattern. The earlier ones use the early Hemi pattern. I think the change was in '60-61.

There are parts out there for the Poly, just not readily available through the chain stores. Hot Heads Research might have some stuff. And I read that CPPA is coming out with a new 4bbl intake developed with Hot Heads for the Poly.

For a frame swap I'll encourage the Dak before the S10 to keep it in the family. Also there have been some guys that have already done it. There are a couple build threads on Moparts. I'd use an '87-96 Dak donor, preferably a '92-96 V8 to start with, then swap on the '87-90 5-lug front rotors and swap in the same year ear axles.

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