Vincentc
Legendary Member
- Joined
- Jun 3, 2008
- Messages
- 1,514
- Status
- OWNER - I own a Hatteras Yacht
- Hatteras Model
- 43' DOUBLE CABIN (1970 - 1984)
After flushing the engines raw water system I started replacing the engine zincs.
I noticed there were brass plugs just below were the raw water lines enter and exit on each end of the 1983 Detroit 671 TI intercoolers ..
The plugs looked like the smaller engine zinc plugs so I undertook to remove the rear plug on the port engine intercooler.
Using a socket wrench I turned the plug maybe a half turn before it broke. I bought a 1/8" NPT tap and the recommended drill bit.
Before using a drill motor I inserted the bit in the depression left where the plug broke and turned it by hand with vice grips.
Simply turning by hand the drill bit broke thru the remainder of the plug.
I worked the bit around by hand and then used the tap to clean out the threads.
I then removed the rear intercooler plug on the starboard engine. It came out without drama; however, it is simply a brass plug without a hole for a pencil zinc.
Assuming the IC only had one zinc, I removed the forward forward plug to replace the zinc that must be there.
It turned out to be another plug with no place for a zinc.
I have new plugs with zincs that fit the holes. Should I install zinc(s) in the intercoolers or leave them like they were?
I also had a similar issue with the inside zinc on the starboard end of the heat exchanger on the port engine.
This zinc plug also broke off after a part turn. It is almost inaccessible.
There was no way I could drill and tap it without removing the Heat Exchanger from the engine.
I was able to drill a hole through the center of the plug then insert a 3/8 bolt used rubber and stainless washers inside and out to seal the opening.
It seems to me that one zinc for the heat exchanger should be sufficient.
Why the port engine should have issues that the starboard engine does not is puzzling.
Look forward to your good advice.
Thanks
I noticed there were brass plugs just below were the raw water lines enter and exit on each end of the 1983 Detroit 671 TI intercoolers ..
The plugs looked like the smaller engine zinc plugs so I undertook to remove the rear plug on the port engine intercooler.
Using a socket wrench I turned the plug maybe a half turn before it broke. I bought a 1/8" NPT tap and the recommended drill bit.
Before using a drill motor I inserted the bit in the depression left where the plug broke and turned it by hand with vice grips.
Simply turning by hand the drill bit broke thru the remainder of the plug.
I worked the bit around by hand and then used the tap to clean out the threads.
I then removed the rear intercooler plug on the starboard engine. It came out without drama; however, it is simply a brass plug without a hole for a pencil zinc.
Assuming the IC only had one zinc, I removed the forward forward plug to replace the zinc that must be there.
It turned out to be another plug with no place for a zinc.
I have new plugs with zincs that fit the holes. Should I install zinc(s) in the intercoolers or leave them like they were?
I also had a similar issue with the inside zinc on the starboard end of the heat exchanger on the port engine.
This zinc plug also broke off after a part turn. It is almost inaccessible.
There was no way I could drill and tap it without removing the Heat Exchanger from the engine.
I was able to drill a hole through the center of the plug then insert a 3/8 bolt used rubber and stainless washers inside and out to seal the opening.
It seems to me that one zinc for the heat exchanger should be sufficient.
Why the port engine should have issues that the starboard engine does not is puzzling.
Look forward to your good advice.
Thanks
