Mopar 318 rockers

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JBMMV

JBMMV

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Location
Poligny / France
Hello from France!

I just bought a 1970 Plymouth Duster with a 1978 Mopar 318 to complete my little collection of old cars...
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I now have the choice :) :steering:

I have certainly a rocker problem on the 318ci. I have a hydraulic pushrod that has passed through a rocker.

I think some rockers are in the wrong place.

Left side (driver), I have from left to right: 72LT / 712RT / 72LT / 712RT / 72LT / 712RT / 72LT / 712RT

Right side (passenger), I have from left to right: 712RT / 712RT / 72LT / 712RT / 72LT / 712RT (which is the one the pushrod perforated) / 72LT / 72LT

The ancient owner had disassembled the cylinder heads to change the hydraulic lifters, and I think he did not put them back in the correct order.

Here's some photos. Thanks for your answers! :thankyou:

mopar1.jpg
mopar2.jpg
mopar3.jpg
 
Stock cam and valve springs or aftermarket? I've seen that happen with high valve spring pressure. 65'
 
What is the difference between a 72LT and 712RT?
The 72LT is for exhaust and 712TR for intake?

So I should, on each side (driver and passenger) have from left to right:

72LT / 712RT | 712RT / 72LT | 72LT / 712RT | 712RT / 72LT
That's it ?
 
I have seen several like that over the years on stock 318 and 340-360. valve stuck when firing the engine up or just a weak rocker. Piston may have had to close the valve . It doesn't look like its getting much oil up top. Change the oil and filter. Make sure that lifter didn't come out or apart.
 
Thanks. I'll change all the rockers and pushrods to be sure. But what should be the order of rocker arms for each side?
 
Hello!

Sorry to insist, but I didn't get the answer. What should be the order of the rockers?
L-R / L-R / L-R / L-R?

If this is it, does this mean that an L (or R) rocker can be used for both an intake valve and an exhaust valve?

I thought the L were for exhaust and R for intake, when looking at my engine...

Thanks.
 
JBMMV said:
Hello!

Sorry to insist, but I didn't get the answer. What should be the order of the rockers?
L-R / L-R / L-R / L-R?

If this is it, does this mean that an L (or R) rocker can be used for both an intake valve and an exhaust valve?

I thought the L were for exhaust and R for intake, when looking at my engine...

Thanks.
Click to expand...
This is the correct order. The rockers are oriented left and right in each pair, for each cylinder.

So yes, the L or R can be on an exhaust or intake valve.

Glad you got this car! You are in a nice part of France!
 
Not from France... just been in the area once, traveling. You're getting over near the Alps, where the scenery gets pretty, as I'm sure you you know.

My main ancestry is out of the middle Rhine region.... 8 or 9 generations ago. They were Baptists, who were probably part of the big wave of Protestant emigration through England and to America in one of the changes of power between Protestants and Catholic rulers in the late 1600's and early 1700's.

So where are you from Stixx? And sorry for the side discussion, OP!
 
JBMMV said:
Hello!

Sorry to insist, but I didn't get the answer. What should be the order of the rockers?
L-R / L-R / L-R / L-R?

If this is it, does this mean that an L (or R) rocker can be used for both an intake valve and an exhaust valve?

I thought the L were for exhaust and R for intake, when looking at my engine...

Thanks.
Click to expand...


The pushrod 'dimples' should be opposite each other for each pair of valves... Ie - the dimples go on the outside, away from each other...
 
krazykuda said:
The pushrod 'dimples' should be opposite each other for each pair of valves... Ie - the dimples go on the outside, away from each other...
Click to expand...
OK, I understand, so the left rocker must have the dimples on the left and right rockers on the right.

So the two pushrods make like a V
 
Another question about my rockers arms. The 72LT and 712RT are original Mopar parts or not?

And what's the differences between 712RT and 312RT for exemple?

Are there rockers from other brands that could replace them?

Thanks.
 
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Plymouth 65 said:
Stock cam and valve springs or aftermarket? I've seen that happen with high valve spring pressure. 65'
Click to expand...

I contacted the former owner. He told me that his mechanic had just changed the hydraulic tappets. Not the pushrods or the springs.
 
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As far as I know, there is not difference in the numbers on the rockers. They may be difference production year numbers, or just different replacement parts numbers.

By the way, what is the white car at your house? Some sort of Opel? Or a Chevrolet Monza?
 
nm9stheham said:
As far as I know, there is not difference in the numbers on the rockers. They may be difference production year numbers, or just different replacement parts numbers.
Click to expand...

Thanks a lot for this info. I was thinking the number has a rapport with size or thickness...

nm9stheham said:
By the way, what is the white car at your house? Some sort of Opel? Or a Chevrolet Monza?
Click to expand...
It's a 1977 OPEL Manta S, the car that OPEL released to compete with the Ford Capri in the 70s. But yes, It looks like a Chevrolet Monza!
My favorite car, very reliable, fun, comfortable...
Some photos with my latest OPEL Insignia Grand Sport from 2018 :
 
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OK thanks! Very cool!

I like the Insignia... I have been thinking of getting an Insignia wagon for the wife.....2020 is the last yer Buick will sell them in the US.

I have a '75 Ascona A, and a '72 Manta A rally project. Rallied both a Manta A and Ascona A in the past. I don't think I ever knew of the Manta S! But those wheels sure do look familiar!

IMG_20190712_151432159 (Small).jpg
 
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