CROSSOVER TUBE and WATER PRESSURE SENDING UNIT

[Jim Bates]

Captains,

I have rewired my A4 (and the entire boat), installing new wiring and all new guages (the old ones did not work) on my 1963 Wayfarer Islander 32 and am almost ready to see if I can get her to start (we did the "A" job on all the rewiring according to ABYC standards with new Bluesea electrical panels). However, I may have a slight problem with the water cooling system setup (but it ran fine before I started on this endeavor) (but it ran without the water temperature guage working). Oh, I have an early model A4.

My water temperature system looks like Diagram B on page 7-3 of the Moyer Service and Overhaul Manual.

CROSSOVER TUBE: I took off the old crossover tube and the hole in the top of the exhaust manifold has a metal plug in it.

The old water temperature sending unit was connected to the middle of the crossover tube (old school).

I have ordered a new crossover tube today (which I understand will come with new gaskets) but need to know what to do about the metal plug in the exhaust manifold. Do I take it to a machine shop and have the plug drilled out? Or do I have to buy a whole new manifold. There must have been a reason why a prior owner put a plug in the exhaust manifold. Any ideas? Or am I left to finding out when I start her up?

I have removed the exhaust manifold and it is clean. (Although I broke off the head of the drain plug on the side of the manifold when I tried to remove it).

WATER TEMPERATURE SENDING UNIT:

There is a T coming out of the top of the back of the exhaust manifold.

I have a brand new ISSPRO water temperature sending unit that will attach to the guage. I have seen pictures where this is attached to the top of the T fitting. Is this where it goes? If so, what do I need to attach it? If not, where do I put it?

(I have pictures of all this but this is my first post and I can't figure out how to make the pics smaller, they are huge on preview).

I believe these are the last two items I need to take care of before I start her up (and go to the yard). Any assistance you may offer would be greatly appreciated.

Jim

[Skywalker]

Please try to reduce he size of the pictures, it will help tremendously.

You have an early model A4, right?

Chris

[Marian Claire]

First off welcome to the forum. I also have a early model and I do not see how it could be functioning properly with the manifold inlet plugged. Can you discribe your cooling system from end to end. FWC, fresh water cooled or RWC, raw water cooled? The T at the manifold exit is where I have my temp sending unit. Dan S/V Marian Claire

[Jim Bates]

Here are some pics.











I am going to boat tomorrow and will draw a diagram. I have other pics of water system but they are piecemeal as they are behind engine and plywood.

[Jim Bates]

Also, I do have the early model engine (boat is a 1963) and it is raw water cooled.

[Marian Claire]

That is one interesting crossover tube. Dan S/V Marian Claire

[hanleyclifford]

That is not a metal plug, but the hole sure is "plugged"! I think you are going to find that manifold is very plugged throughout the chamber.

[Jim Bates]

Clifford was spot on! I took my chisel and hammer and chipped away at the hole where in the exhaust manifold where the cross-over tube inputs. It was in fact stopped up - no plug.



I then decided that I better take the water jacket cover plate off and its was fouled as well.



The water jacket cover plate was fouled.



I cleaned up the interior of the water jacket with a hammer, chisel and file. I took the nozzle of the wet/dry vac and sucked out everything in there.



Water runs freely from end to end of the exhaust manifold but next weekend I will perform a more detailed flush described in the Moyer Manual. Also going to order a new water jacket cover plate and perform the high pressure flush of the engine with the garden hose per MM manual.

I am going to stick that water temperature sending unit in the T at the end of the manifold.

This engine if 50 years old - who knows how long this condition has existed.