Adding a Thermostat to Perkins 354

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Mrwesson

Senior Member
Joined
Aug 4, 2016
Messages
415
Location
United States
Vessel Make
1979 Mainship 34
My thermostat has been removed and while not extremely difficult it's not at all convient to access/remove the thermostat housing.

Engine is running at around 120 degrees and very smoky(Bad).

I was thinking of adding one of these but unsure at what point in the lines I should add it.

21vRCx9IH1L.jpg


This would allow me to easily access the thermostat in the future without removing 12 bolts and then some. Another bonus would be I could pinch/cap the lines so I don't have to drain all the coolant beforehand.

Where would you put it on a Perkins 354 160hp(turbo)?
 
Need more info than what you have offered to give a creditable opinion but In the hose between the existing T.S. hsg. and the heat exchanger would be a guess at this point.

I think though that this is not going to work the way you intend.

Your proposed stat must be exposed to the coolant flow, not just near it, to sense the coolant temp. so it can open. Failure to do that causing slow or improper reaction to the rising temps could lead to an overheat.

Many T.S. do not just simply open/close. There are other passages in the housing that as one opens, another closes to force coolant to where it needs to go. Otherwise it will go wherever it darn well feels like going not cooling the engine. In other words as the engine heats and the stat reacts and it opens allowing coolant to reach the heat exchanger but also closes the bypass passage to force that coolant into the exchanger. If that bypass passage is not closed then the coolant will not reach the heat exchanger but simply continue to circulate in the engine and not cooling.

Just opening/closing the hose to the heat exchanger may not be enough.

Be very carefull or you could cost yourself far more than some inconvenience.

It might help if you posted a link to where you found this thing for a better opinion.

Changing T.S. should not be a big deal if coolant is changed and maintained properly. Most engines don't need a stat change but once in ten or more years. DO you need to change yours more often. If so, why?
 
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Perkins 354's were not designed to be easy to work on, but the labor involved in changing out the thermostat should be considered a necessary evil.
As mentioned above, you will probably not need to do this again for a long time.
 
C Lectric, is exactly correct in his post, Most thermo stats when opening close off a gallery that forces the water around the engine and through the heat exchanger etc,

Most people dont realize that if removing the thermo stat you need to block off the one or two galleries(such as Volvo) that the thermostat closes when it opens,(some one may have done this on yours already?)

The real issue with out plugging the galleries one day the water may just decide
to circulate around the block and thus over heat, (very hard to diagnose these issues when people remove their thermo stats ,

Bottom line: If engine builders thought they could save $20 they would!! but even the latest engines still use Thermo stats

A good quality thermo stat with added coolant should last way more than a few years:thumb:

Cheers Steve
 
Why was the thermostat removed? I could guess why but would rather not.
120 is too cold to run the engine at. It is below the design temp.
 
My guess is that there is an overheat problem somewhere else in the cooling circuit that inspired removal of the thermostat.
The Perkins motors that I have worked with/on show some particularly poor engineering choices in the cooling department!
 

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