Recent Topics
I'm finally retired!
by grampi - 05/30/20 07:20 AM
2020 Equinox 1.5t
by IMPALA08 - 05/30/20 07:05 AM
Infineum article and resource repository
by Gokhan - 05/30/20 05:02 AM
TPMS problem
by rrretiree7 - 05/30/20 02:17 AM
I need your help picking out fireworks for a show.
by joegreen - 05/30/20 12:13 AM
Best off the shelf oil for the price
by samiamz - 05/30/20 12:09 AM
I upgrade my car
by miden851 - 05/30/20 12:00 AM
Ford PVD Wheels Defects
by kstanf150 - 05/29/20 07:48 PM
General thoughts on high milage oils.
by tblt44 - 05/29/20 07:09 PM
Jeep Wrangler JL
by dishdude - 05/29/20 06:43 PM
Valvoline MaxLife 5W-20
by Jackson_Slugger - 05/29/20 06:33 PM
Yamaha dry sump PWC and oil level sensitivity.
by ledslinger - 05/29/20 06:30 PM
WSS-M2C946-B1 vs WSS-M2C961-A1
by W9HDG - 05/29/20 06:16 PM
Waterfall Eco Dynamic tires
by Saabist - 05/29/20 05:55 PM
O’reilly clearance
by Gonz - 05/29/20 04:56 PM
2016 Overland Jeep Wrangler Oil/Filter
by Since1941 - 05/29/20 04:24 PM
Newest Members
RedMan542, bdubb, TreePointer, PierreS, GDR
71572 Registered Users
Who's Online Now
90 registered members (2015_PSD, ARB1977, 53' Stude, alarmguy, askani79705, Bailes1992, 6 invisible), 1,771 guests, and 27 spiders.
Key: Admin, Global Mod, Mod
Forum Statistics
Forums67
Topics306,038
Posts5,285,308
Members71,572
Most Online4,538
Jan 20th, 2020
Donate to BITOG
Print Thread
Hop To
Page 1 of 2 1 2
Thermostat housing gasket leaking #5388862 03/29/20 06:58 PM
Joined: Nov 2009
Posts: 5,959
M
motor_oil_madman Offline OP
OP Offline
M
Joined: Nov 2009
Posts: 5,959
So I changed the thermostat housing gasket on my boat, fired it up and this one is doing the same thing. The gasket looks like it absorbed the coolant and is now wet. The old one was just a tiny seep. I think it lost maybe 8 oz over 20hrs. I don't know what to do now..... I used some good thick gasket maker so I'm surprised. Maybe the cover is warped.


2007.5 dodge cummins 6.7 liter. Chevron Delo400 15w40. 7000 mile or 250-300hr intervals.

Re: Thermostat housing gasket leaking [Re: motor_oil_madman] #5388875 03/29/20 07:12 PM
Joined: Jun 2008
Posts: 6,354
ls1mike Offline
Offline
Joined: Jun 2008
Posts: 6,354
Engine type?

I had a warped housing a few times on my 1989 BBC. Replace the housing leaked stopped.


Mike
00 Trans Am WS6 5.7 LS1
17 Silverado 3500HD 6.0
14 Caprice PPV 6.0
15 Malibu LTZ Turbo
12 Passport TT
Re: Thermostat housing gasket leaking [Re: motor_oil_madman] #5388876 03/29/20 07:15 PM
Joined: Jun 2003
Posts: 20,824
C
Chris142 Offline
Offline
C
Joined: Jun 2003
Posts: 20,824
Put the housing on something flat and see if its warped. If it is grind it in circles or file it till it's flat.


02 Wrangler Napa high milage 10w40
87 F250 Valvoline 15w40
07 fjcruiser Car lube plus 10w30
Z400 castrol T 10w40
Can am Maveric edge 5w40
57 case tractor Chevron sae30
Re: Thermostat housing gasket leaking [Re: motor_oil_madman] #5388877 03/29/20 07:16 PM
Joined: Nov 2009
Posts: 5,959
M
motor_oil_madman Offline OP
OP Offline
M
Joined: Nov 2009
Posts: 5,959
350 Chevy


2007.5 dodge cummins 6.7 liter. Chevron Delo400 15w40. 7000 mile or 250-300hr intervals.

Re: Thermostat housing gasket leaking [Re: motor_oil_madman] #5388883 03/29/20 07:20 PM
Joined: Jun 2008
Posts: 6,354
ls1mike Offline
Offline
Joined: Jun 2008
Posts: 6,354
Housing, they are cheap. Get one and try it out.


Mike
00 Trans Am WS6 5.7 LS1
17 Silverado 3500HD 6.0
14 Caprice PPV 6.0
15 Malibu LTZ Turbo
12 Passport TT
Re: Thermostat housing gasket leaking [Re: motor_oil_madman] #5388885 03/29/20 07:23 PM
Joined: Jul 2017
Posts: 142
9
928 Offline
Offline
9
Joined: Jul 2017
Posts: 142
If you have one of those cheap mr gasket type chrome ones, throw it out & get a cast iron one.

Re: Thermostat housing gasket leaking [Re: motor_oil_madman] #5388911 03/29/20 08:03 PM
Joined: Oct 2011
Posts: 2,016
U
user52165 Offline
Offline
U
Joined: Oct 2011
Posts: 2,016
Did you remove 100% of old gasket and residue?

Re: Thermostat housing gasket leaking [Re: user52165] #5388932 03/29/20 08:31 PM
Joined: Nov 2009
Posts: 5,959
M
motor_oil_madman Offline OP
OP Offline
M
Joined: Nov 2009
Posts: 5,959
Originally Posted by user52165
Did you remove 100% of old gasket and residue?


Yes


2007.5 dodge cummins 6.7 liter. Chevron Delo400 15w40. 7000 mile or 250-300hr intervals.

Re: Thermostat housing gasket leaking [Re: motor_oil_madman] #5388972 03/29/20 09:22 PM
Joined: Sep 2007
Posts: 879
Driz Online Content
Online Content
Joined: Sep 2007
Posts: 879
Some Mercruiser have a ground (of all things) via the gasket. That’s why you need a marine, mercruiser or Sierra, not regular chevy car or homemade one. It screws up one of the sending units or gauges at least on mine unless you ground another way. Just so you know😇.
Check the mating surfaces for square. Use a short ruler or straight edge to check flatness. If it’s off and not cracked just sand it flat with a small block of 2x4 ect and some black 220 Wet n Dry sandpaper. It should true up fast.

Re: Thermostat housing gasket leaking [Re: motor_oil_madman] #5388998 03/29/20 10:06 PM
Joined: Nov 2009
Posts: 5,959
M
motor_oil_madman Offline OP
OP Offline
M
Joined: Nov 2009
Posts: 5,959
I don't think it did. It was just a gasket, no metal or anything.


2007.5 dodge cummins 6.7 liter. Chevron Delo400 15w40. 7000 mile or 250-300hr intervals.

Re: Thermostat housing gasket leaking [Re: motor_oil_madman] #5389176 03/30/20 07:49 AM
Joined: Apr 2010
Posts: 5,867
J
jeepman3071 Offline
Offline
J
Joined: Apr 2010
Posts: 5,867
Get a new thermostat housing, use a gasket with a thin layer of Permatex "right stuff" gasket maker on both sides. Wait about 30 min and make sure the bolts are torqued to spec. Also be sure the thermostat is sitting properly in the engine, I've seen a few sit crooked and cause a leak.


1998 Jeep Wrangler Sahara 4.0L/5MT (157k) - PHM 10w30, Wix 51085
2009 BMW 328i N51 (61k) - Liqui Moly 5w40, MANN HU816X
Re: Thermostat housing gasket leaking [Re: motor_oil_madman] #5389184 03/30/20 07:59 AM
Joined: Dec 2003
Posts: 1,371
W
wings&wheels Offline
Offline
W
Joined: Dec 2003
Posts: 1,371
Originally Posted by motor_oil_madman
I don't think it did. It was just a gasket, no metal or anything.

If you have a sender in the housing above the gasket, you need the marine gasket which has a metal button to provide a ground. If no sender in that location, you are OK. There are also a number of variants and revisions to that cooling system over the years to add confusion. I just went through this. seepage and all, on our old Century Resorter w/ the same motor. After talking to a few folks w/ experience, I finally settled on the Mercruiser gasket set w/ Permatex High Temperature RTV as a dressing. Unless your housing is really warped, some smoothing and this should be good.

What type of boat?


'05 Lotus Elise S/C
'85 Land Rover 90 diesel
'74 Triumph TR6
'74 BMW 2002
'72 Land Rover Series III 88"
'99 Porsche 996
'01 Porsche Boxster S (mostly Wife's...)
'19 VW Golf R (Wife's)
Piper Pa28-236


Re: Thermostat housing gasket leaking [Re: motor_oil_madman] #5390532 03/31/20 10:45 PM
Joined: Nov 2009
Posts: 5,959
M
motor_oil_madman Offline OP
OP Offline
M
Joined: Nov 2009
Posts: 5,959
Well maybe it was a residual drop of coolant cause before it would leak a tad just sitting there dead cold.


2007.5 dodge cummins 6.7 liter. Chevron Delo400 15w40. 7000 mile or 250-300hr intervals.

Re: Thermostat housing gasket leaking [Re: motor_oil_madman] #5396885 04/07/20 09:37 PM
Joined: Nov 2009
Posts: 5,959
M
motor_oil_madman Offline OP
OP Offline
M
Joined: Nov 2009
Posts: 5,959
Nope she leaks like a sive.


2007.5 dodge cummins 6.7 liter. Chevron Delo400 15w40. 7000 mile or 250-300hr intervals.

Re: Thermostat housing gasket leaking [Re: motor_oil_madman] #5396887 04/07/20 09:37 PM
Joined: Nov 2009
Posts: 5,959
M
motor_oil_madman Offline OP
OP Offline
M
Joined: Nov 2009
Posts: 5,959
Gonna take a sanding block to it and get it flat. I haven't seen if it's warped, but it must be.


2007.5 dodge cummins 6.7 liter. Chevron Delo400 15w40. 7000 mile or 250-300hr intervals.

Page 1 of 2 1 2
Previous Thread
Index
Next Thread

BOB IS THE OIL GUY® Powered by UBB.threads™