Cooling flow diagram

[rigspelt]

Here is a basic cooling flow diagram I made up to donate to the forum. If anyone wants one in a different format, PM me. Get the MMI manual and accompanying notes for more complete information.

I am not at all familiar with early model A4s. Please correct me if I am wrong with either of these diagrams, since I am not an expert on engines.

UPDATES: 11 July 2010 - slightly revised late model diagram, and added early model draft diagram.

[domenic]

Thank you for this.

[Dave Neptune]

Nice

Hey Rigs, nice job especially showing the diverter!!!! I have seen many a side plate at a friends shop with just a Tee fitting~~not good. He stated that some customers say that they get "more water" through the Tee than the diverter~~bad idea!

Dave Neptune

[rigspelt]

I've been asked to add an early model flow diagram. See the original post in this thread. I am not at all familiar with early model A4s, so please comment if something is not right.

[67c&ccorv]

I've been asked to add an early model flow diagram. See the original post in this thread. I am not at all familiar with early model A4s, so please comment if something is not right.

Looks good to me Rigsy...my manual is up at the boat. I'll bring it home and scan the diagram.

[captainmurph]

Thanks for the cooling diagram post!

Although this is an old post, I'm glad I discovered it.

I am working on my Cal 30 which has had a newer (1975) motor installed but never really operated.

It appears that the PO used stuff from the old installation and put it on the newer engine.

I couldn't figure out why I had a T at the water pump and also at the exhaust manifold outlet.

Now I can see that they don't need to be there. It will make it much easier to plumb since I'm replacing all of my hoses.

Murph

S/V Amalia
1965 Cal 30

[Marian Claire]

Yep. Rigs did a great job with the diagrams. Your diagnosis is spot on. Early model cooling blended into a late model. Dan S/V Marian Claire

[roadnsky]

Don't forget folks there is a dedicated section on this site that has all kinds of great drawings posted there.
Admin Bill went to the trouble of setting it up...
we should put it to use.

http://www.moyermarine.com/forums/forumdisplay.php?s=&f=80&page=1&pp=35&sort=lastpost&order=desc&daysprune=-1

[ndutton]

Although the older Dole system is preferred by many, the diagram demonstrates it's drawback. While the engine is cold and warming up there is reduced water flow to the exhaust.

Vetus waterlifts in particular are very sensitive to elevated exhaust temps.

[Marian Claire]

One of the reasons I use the original, or my version of such, pre-Dole T stat set up. But I have blabbed on about this before. Dan S/V Marian Claire

[pdecker]

What is the difference between the diverter and tee fitting?

I am tackling my cooling water issues this week on my RWC late model engine. What's the difference between the diverter and the tee fitting? Is the diverter a valve? Can it be cleaned out?

[roadnsky]

...What's the difference between the diverter and the tee fitting? Is the diverter a valve? Can it be cleaned out?

The T-Fitting is on the side of the Water Jacket allowing water flow to go in two directions.
The Diverter is a part of the T-Fitting that is just inside the Water Jacket.
It diverts the cooling water flow aft towards the #4 cylinder.
(Ideally, aft and at a 45° down angle)

Rigs diagram above points out both.

Both should be cleaned periodically as well as opening up the Water Jacket and cleaning out the inside passages.
There are quite a few threads about doing this procedure.

[Brent W]

So I'm a new A4 owner and learning a lot here. One thing I get confused with often...

People are discussing the cooling system, but I don't know if they are talking "Raw water" or FWC.

When is there a significant difference in maintenance, operation, and troubleshooting? It would seem like the FWC is way less prone to problems, being less corrosive and a CLOSED SYSTEM.

Thanks

BW

[JOHN COOKSON]

People are discussing the cooling system, but I don't know if they are talking "Raw water" or FWC.

When is there a significant difference in maintenance, operation, and troubleshooting? It would seem like the FWC is way less prone to problems, being less corrosive and a CLOSED SYSTEM.
BW

Most of the time we don't know if the owner has RWC or FWC. It is necessary to ask.
A FWC system has a different problem set than a RWC system. In general if a FWC system problems are with the FWC apparatus and a RWC problems are inside the engine itself. Which would you rather have? When one converts to a FWC system the engine cooling passages are made as squeaky clean as possible. The initial cleaning plus antifreeze coolant makes for much improved cooling and zero engine corrosion.

TRUE GRIT

[Joe/Ct]

Cooling System Hose Replacement

Guys,

I sprang a leak in the hose going from the water pump to the "T" on the side plate. What is the proper procedure for replacing? Do I need to remove the alternator, the distributor and the water pump?

Thanks, Joe
Irwin Comp30
Blueberry Pie