The trap of the industrial / motorhome 318-3

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67Dart273

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Seems like folks are always asking about these. Here's a customer from another forum who fell into the trap. Swapped intake, then it leaks.....................

These engines use a lot of "weird" hardware on the front of the engine, with a "high mount" water pump. Notice the cartridge oil filter. Notice the timing mark is special. But the big trap is............

the cylinder heads. Not only do some of these use the big Ford style 18mm tapered seat plugs, but the HEAT CROSSOVER is COOLANT and not exhaust.

This means that if you install a light truck/ car intake, with EGR you are going to have coolant injected into the intake/ cylinders, and depending on what intake and how well it's sealed, you still might have a leak to the exterior of the engine.

The clue is the heat crossover port in the heads. Instead of having the telltale crescent around the top of the port, these just have the port.........coolant

The bottom photo is the coolant supplied crossover, the photo above is the conventional car/ light truck heads

http://www.mymopar.com/forums/index.php?showtopic=17858&st=0&gopid=50725&#entry50725

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View attachment crossover.jpg

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You know that's interesting. The early Hemi truck heads are the same way. The center port is not an exhaust crossover, it's coolant so you have to use the right intake.
 
This is something to remember for future hunts for 318's. Did they do the same for RV 360's???
 
I'm not sure. I'd be leary of anything that's ***-3 on the pal - ooh - tion sticker.


RB engine...................... These are easy to spot because the high mount pump housing connects to ports in the fronts of the heads. If you look at the photo showing the exhaust, you can see a TEMP SENDER sticking out the very middle - above the top of the exhaust manifold. These are wet there, and coolant crossover
 

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If I remember right, the 318-3 crank was the premium one everyone wanted back in late '60s/early '70s because it was forged.
 
Ok so I will ask the dumb question of the hour. Why do they have the water pump so high?
 
yup, I got one of them 318-3 premium engines in my 66 Barracuda, runs great bone stock 2 bbl,
a couple more things that are different about them are
1: the pistons are 1.658 compression height, instead of 1.741
2: the heads are only 57cc
3: they came stock with a double roller timing chain
 
I have a 1978 RV 360, funny thing is; no raised water pump, has EGR intake but factory blocked with plate. and it does have 18MM plugs...???
 
these are the 234 heads I've mentioned before that a lot of people on here didn't believe existed wiith the blind exhaust ports, *no more flow loss due to the exh cross over*

A '67 only head.

And you can block the water cross over...
 
What in your opinion is the best way to do so?

I used the same thin metal and rtv method I use when I block it as an exh port instead of water. Worked great, those are thee best factory 318 heads imo. I say that because in reality an open chamber head will flow more modified the same as a closed chamer and the exhaust ports are blind...now you don't have one weak exh port per head.
 
If the heads or intake are milled for .030 -.060 felpro gaskets, or even just outright except them...the gasket will crush and the metal won't cause any distortion of the intake or or seal problems.
 
No intention on thread high jacking,,,, but Are there any other various pit-fall blocks we have to be concerned with?

People talk about school bus's with 'supposedly discontinued 413's, etc.

Besides rotating the opposite direction, how about boat blocks (360 or big block)? Any thicker cylinder walls? Can we use them? or avoid them- Is the alloy the same?
 
I would say steer clear of the RB 383 engines, the 413, the 361 and the 350.....simply because piston choices are not there. You'd have to get custom pistons made. They are not bad engines. They are the same tried and true B engine design but parts availability makes them expensive to build.
 
I don't know. Over 400 bucks for 426 wedge pistons, and they are cast. I don't call that reasonable for cast. LOL
 
a buddy down the road from me built a 400 wedge from a 413 block (I think it was anyway) put down really good numbers and worked well!

engine was from early 70's motorhome
 
No intention on thread high jacking,,,, but Are there any other various pit-fall blocks we have to be concerned with?

People talk about school bus's with 'supposedly discontinued 413's, etc.

Besides rotating the opposite direction, how about boat blocks (360 or big block)? Any thicker cylinder walls? Can we use them? or avoid them- Is the alloy the same?


Only real caveat I know on marine CCW engines --other than water jacket damage on ones with no heat exchanger--is the oil slinger slots on the crank seal go the wrong way.
 
I was under the impression that not every RV/motorhome got an industrial engine. The 440 in my brother's Dart came out of a '73 28ft Titan motorhome and it did not have the high water pump and matching heads. It did appear to be the original engine by all accounts.
 
these are the 234 heads I've mentioned before that a lot of people on here didn't believe existed wiith the blind exhaust ports, *no more flow loss due to the exh cross over*

A '67 only head.

And you can block the water cross over...

Are you talking about the heads on the engine in Del's photo? What exhaust did you run? The industrial/motorhome heads have a different dedicated exhaust bolt pattern
 
I was under the impression that not every RV/motorhome got an industrial engine. The 440 in my brother's Dart came out of a '73 28ft Titan motorhome and it did not have the high water pump and matching heads. It did appear to be the original engine by all accounts.

You're right not all of them did. Where did somebody say they all did?
 
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