Blocked Manifold Coolant Passage

[sastanley]

Jerry, do I detect a copper pipe fitting on your PCV hook-up? That's how I did mine.

Looks like the standard Indigo PCV kit to me. That was the first "mod" to my A-4

[tartansailboat]

manifold coolant problem

greg, that brass tee that I see in the place where the temperature gauge normally goes, is that for the temp gauge and a temp alarm? If so, did you temp reading change much from the original position directly in the block. I am going to install a variation of that tee with a three way valve to be able to flush the engine without taking the thermostat out and my temp guage will be in the same place as yours.

BTW, I am in Brickyard Cove in Richmond.

[Dave Neptune]

Hot spot

Hi guys, i finally got to the boat last night and yes I have the same discoloration on my manifold. It has been on the block for 4 years since my last acid flush episode. She still runs cool and the temp stays right where it always does.

Don, perhaps you could chime in hear~~~Does a Tee fitting on the outside of the Temp sending position affect the temp reading much when installing an alarm or flushing port?

Jerry, yeh go copper. I have installed in 6~8 places copper Els & 45's to get around tight corners. Now my aft cockpit actually drains well and no more kinking hoses there.

Dave Neptune

[Don Moyer]

Dave,

As a practical matter, temperatures routinely vary in late model by-pass cooling systems depending on raw water temperature, power settings, etc, to the point that it's difficult to be too scientific. Reports have accordingly been somewhat mixed on the affect of installing a "T" in front of the head. Those seeing a discernable difference in temperature before and after installing a "T" have reported variations of up to 5 degrees on the cooler side.

Don

[Greg]

The "Tee" is for the sender and high temp alarm. I'm not sure if it affected the gauge reading as I put in the new MMI thermostat upgrade .. and was running too cold prior. My gauge looks to be the original (37 yrs) so that is suspect too.
As for the hot spot(s) .. I'm holding off pulling the manifold for now. It seems isolated to the end of the manifold and the gasket looks good w/o leaks. It appears 5 of us have the same thing. Think I'll borrow a heat gun from work and shoot the manifold when up to temp and see what I find. It will give me a chance to record some numbers around the engine for later use.
In my Ericson .. as is the case with most of our installs, once I put the fuel tank and starboard bulkhead back in .. the only limited access is to the front of the A4. I'm trying to get everything dialed before doing so. Entering and exiting my marina is a narrow runway with 4 to 6 knots of current abeam at the wrong time. My Atomic needs to be a trusted friend.

Any advise / comment on the heat at the front of the manifold(s) Don ?

As always .. I appreciate the forum and everyones contributions.

Regards, Greg