amg_rx7 Dork
8/9/12 8:43 p.m.

I'm helping a friend work on his old Dodge truck (Ramcharger?) 4x4. At one point in it's life, a van body was grafted to the truck frame but that shouldn't matter to the point of this thread... It has a 318 ci V8 and a manual trans.

Anyway, I was working on the coolant system and replaced the tired, old, frayed radiator hoses with new ones from O'Rielly's The new bottom radiator hose felt a bit loose when slipped over the inlet / outlet at the bottom of the radiator and at the block so I tightened the crap out of the hose clamps hoping that would hold. It didn't...

Is that bottom hose supposed to be a different diameter than the thermostat outlet hose that goes to the top of the radiator?

Need some urgent help on this.


amg_rx7 Dork
8/9/12 8:44 p.m.

PS - of course we don't know if the engine is original to the truck. It could potentially be a 318 V8 from a different Dodge.

chandlerGTi HalfDork
8/9/12 9:29 p.m.

In my 77 power wagon the bottom hose was different sizes at each end. However, in my 78 warlock it was the same; may have been which radiator was installed.

Sorry that didn't really help you.....

Rob_Mopar Dork
8/9/12 9:30 p.m.

Yes, they used two different diameter hoses. Lower radiator hose is 1 3/4" inner diameter. Upper is 1 1/2".

My guess is the radiator is from something else.

Not that it will help with the inner diameter problem, but make sure there's a spring in the lower hose to keep it from collapsing too.

And post some pics of this rig.

novaderrik SuperDork
8/9/12 9:55 p.m.

all i know about 70's Dodge V8's is that they had no compression and they still felt the urge to put a gear reduction starter on them for some reason..

amg_rx7 Dork
8/9/12 10:38 p.m.

I'll have to check the sizes but both the radiator and the outlet on the block is SMALLER in diameter than the upper hose which is 1.5"

Does that jive with your experiences?

EDIT - 1.5" inner diameter

amg_rx7 Dork
8/9/12 11:02 p.m.

Actually, I wonder if the hose I got from O'Rielly's is actually 1 3/4 and the truck takes a 1 1/2" diameter....


bearmtnmartin Reader
8/9/12 11:41 p.m.

What I can tell you is that a 1978 Chrysler wagon with 0 miles on a brand-new 318 engine will comfortably go 2 hours without a drop of oil in the engine if the factory does not attach the oil filter adaptor correctly and the new owner ( aka Mom) ignores the bright red light glowing on the dash. No idea about belts though.

Rob_Mopar Dork
8/10/12 9:06 a.m.

I forgot, somewhere around '78-80 Chrysler made some changes to the cooling system. Mostly in the thermostat & housing area.

Depending on the model, they could have had a stepped lower hose. A little digging turns up a molded hose that's 1 1/2" - 1 3/4"

NAPA # NBH 7344

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