1993 Mercruiser 4.3 v6 temperature sending unit

dlogvine

Master Chief Petty Officer
Joined
May 4, 2015
Messages
839
I am assembling 1993 mercruiser 4.3 v6. I had a block with heads and to get accessories I bought an older 1986 Larsen with 4.3 v6 engine. However there are some differences. One of them is the location of the water temperature sender. On the newer engine it is in the thermostat assembly, and there are two sending units. This one 1986 engine has only one sender, and it is sitting in the intake manifold. I'll attach the pictures. My original manifold has a plug in this location and this plug is sitting very solid. I believe to remove it I'd need to heat the manifold and then use the pry bar, remove it. Also I found on the 1986 thermostat housing a hole with a plug that is similar to the hole in the thermostat housing for the temp sender. Can I put the sender into this hole or should I replace intake manifold with the one from 1986 engine. Thx
 

Attachments

  • photo302985.jpg
    photo302985.jpg
    1.6 MB · Views: 1
  • photo302986.jpg
    photo302986.jpg
    1.6 MB · Views: 1
  • photo302987.jpg
    photo302987.jpg
    1.4 MB · Views: 1

Bt Doctur

Supreme Mariner
Joined
Aug 29, 2004
Messages
19,454
If the manifold you want to use has a plug in it, leave it and go with the senders in the therm housing.
If the manifold you plan to use has a sender in it, leave it or remove and plug it and use the senders in the therm housing
 

dlogvine

Master Chief Petty Officer
Joined
May 4, 2015
Messages
839
Thank you guys, that solved the problem. I did not want to remove already installed intake manifold, risking to destroy brand new gaskets. Will just replace the senders position. Or can I use a newer thermostat housing from a newer boat? That one has two sending units and looks like it is fitting. And the second temp sender I can replace with a plug.
 

alldodge

Moderator
Staff member
Joined
Mar 8, 2009
Messages
43,350
Yes you can use the newer style thermostat housing, just need to reroute some hoses.

Old style

V6 83_93 Cooling.jpg


Newer style

V6 Open cooling.jpg
 
Top