Timing Chain

[Greg C.]

I'm taking the coach camping next week for the last time this year. She runs a little warm at 60 to 65, 3/8 or more on the factory gauge. She ran that
temperature all the way from Texas in 95 degree ambient temperatures. It will cool down when I reduce the speed, so from what I have read here, the
radiator is not doing its job. I know the bottom exposed area of the core is pretty beat up from road debris. My plan is to remove it and have it
recored. As has been written here by others, now is the time to do some other work since it will never be easier than when the radiator is out. So I
plan to replace the water pump, timing chain, and fuel pump.

As a lot of the forum threads regarding these are older, and it seems the best choice of parts seems to change with the various Chinese factories
making them at the moment, I would like to ask for recommendations for the best water pump, fuel pump, and timing chain choices.

I've read several threads regarding timing chain replacement. Opinions vary. Most people favor the Cloyes True Roller chain, and that is what I intend
to use. However, some folks advocate the double chain version, while others say there is no reason to use it as the single row chain will outlast the
engine.

Another advantage of the double roller version is the ability to retard/advance cam timing, which I don't think the single roller allows.

So recommendations based on experience, please.

Brand and type of timing chain?

Advance cam timing, or no?

Brand of water pump?

Brand of fuel pump?

Thank you for your opinions.
--
Greg Crawford
KM4ZCR
Knoxville, TN

"Ruby Sue"
1977 Royale
Rear Bath
403 Engine
American Eagle Wheels
Early Version Alex Sirum Quad bags

 

[roy keen]

I’d use the cloud chain and set it advanced
--
Roy Keen
Minden,NV
76 X Glenbrook

 

[Carl Stouffer]

Here's an album I did in the photo site:

http://www.gmcmhphotos.com/photos/g5504-timing-chain-2fradiator-project-05-2f09.html

I ran it straight up, but I think If I had it to do over again, and I had a stock cam, I would advance it 4 degrees. The theory is it will give you a
little better bottom end.
--
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
Solar battery charging. GMCSJ and GMCMI member

 

[Greg C.]

Thank you for the replies.

Carl, I saw from your pictures you had maxed out your floor jack. My radiator looks like it is about 29" tall, with 11" of clearance under the coach
to the bottom radiator mount. I intend to cut mine as you did.

How high would you say I need to jack the coach at a minimum to get the radiator out? The reason I ask is that I am thinking of welding up some super
duty ramps that I can drive the coach up and not have to

use jacks and jack stands. These ramps would be handy for about anything, and be taller than the wood ramps a lot of people build. I'm thinking of 18"
height, which would translate to 29" under the lower

radiator bracket. While it's on the ramps, I intend to replace water pump, timing chain, power steering hoses, engine oil cooler hoses, fuel lines,
etc. I have a radiator shop lined up who will recore the

radiator with 4 row 14 fins per inch for about $500.00, with a 4 day turnaround.
--
Greg Crawford
KM4ZCR
Knoxville, TN

"Ruby Sue"
1977 Royale
Rear Bath
403 Engine
American Eagle Wheels
Early Version Alex Sirum Quad bags

 

[Matt Colie]

Greg,

That is real good price for a recore. I suggest that you get it in writing as soon as you can.

I strongly suggest that you plan to "degree-in" that cam after you install the new chain. It is very easy to make a mistake doing this and it is a
major PITA to correct after the engine is re-assembled.

You might take the time to look at https://help.summitracing.com/app/answers/detail/a_id/4706/~/advancing-%2F-retarding-a-camshaft and plan to
borrow/buy the tools to do this.

Matt
--
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit

 

[Carl Stouffer]

Greg,

If I remember correctly, and after referring to my pictures, I think the cross member was approx 20 - 24" off the ground. It doesn't take as much
height to remove the radiator as you might think. I had the front end up quite a bit higher when I did the engine/transmission R&R a few years ago.

I felt perfectly safe working under there on those stands, and working on the front of the engine was much easier without the padiator and shroud, etc
in the way.
--
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
Solar battery charging. GMCSJ and GMCMI member

 

[Greg C.]

Matt: Do I need to degree in the original cam if I put the replacement timing set in "straight up"? If I don't go with a adjustable timing set, I will
only have one choice for position.

I can understand degreeing the cam if I use the adjustable Cloyes set with several key ways.
--
Greg Crawford
KM4ZCR
Knoxville, TN

"Ruby Sue"
1977 Royale
Rear Bath
403 Engine
American Eagle Wheels
Early Version Alex Sirum Quad bags

 

[Matt Colie]

> Matt: Do I need to degree in the original cam if I put the replacement timing set in "straight up"? If I don't go with a adjustable timing set, I
> will only have one choice for position.
> I can understand degreeing the cam if I use the adjustable Cloyes set with several key ways.

Greg,

It may not be important if you are sure you didn't bump any thing while removing and installing. A problem I have had on more than a few occasions
was that there was enough load on one or more cam followers to move the cam out of position when the timing gear was relaxed or removed. That only
took a few incidents to make this a habit. Unfortunately, I do not have a good idea how to prevent the cam from moving.

It is also less important with a Cloyes set. If it is not a top-line set, all bets are off. Even still, I ran into a counterfeit set in what looked
like a Mopar box once. Fortunately, I did the check and it was wrong. When carefully inspected the box, it said "Mupar" and while all the numbers
were correct, there were other errors. At least I found it before we closed the engine up. "Once bit, twice shy"

Matt
--
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit