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MacGyver
05-03-2009, 06:28 PM
Anyone ever drill small holes in your thermostats to increase cooling on your engines?

Blue Thunder
05-03-2009, 06:39 PM
Its really more to let air pockets out from under the tstat so you don't get hot spots in the engine. It is a good thing on a boat engine. It should not change your cooling though once all in in equalibrium.

Ratickle
05-03-2009, 06:42 PM
I have never heard of that. Any thing else anyone can add?

PatriYacht
05-04-2009, 08:16 AM
It's true, 2 or 3 1/8 dia. holes drilled around the outside of the thermostat allow any trapped air to escape. It also helps to even out the pressure and temperature fluctuations if you run a crossover.

Ratickle
05-04-2009, 08:37 AM
It's true, 2 or 3 1/8 dia. holes drilled around the outside of the thermostat allow any trapped air to escape. It also helps to even out the pressure and temperature fluctuations if you run a crossover.

Thanks Ian.

OldSchool
05-04-2009, 02:47 PM
I don't run thermostats in mine, but I have heard of people drilling the holes in them.

Ratickle
05-04-2009, 04:02 PM
I don't run thermostats in mine, but I have heard of people drilling the holes in them.

I can't imagine not running thermostats up here in Lake Michigan. The water right now is a balmy 44 degrees.I'm afraid the computers on the Empress would think due to temp it was running too rich and keep leaning until it puked.....

MacGyver
05-04-2009, 06:47 PM
I should have posted this earlier. I just changed my stat. But I might pull it back out and do a little drillin'.

cigdaze
05-05-2009, 08:48 AM
I run crossovers on my new engines. I have 150* T-stats in place, and we drilled four 1/8" holes around the perimeter. Temps are perfect and steady. It allows for water circulation through the block at all times including during cold-start and idle to avoid hot-spots and air pockets. It also alleviates the situation where often times when running crossovers with bypasses, the t-stat won't open up due to the raw water dumping on top of the t-stat via the bypass which artificially keeps it cool. It takes a little longer to get up to temp, but I can maintain 150* right on the money.

OldSchool
05-05-2009, 09:17 AM
I run crossovers on my new engines. I have 150* T-stats in place, and we drilled four 1/8" holes around the perimeter. Temps are perfect and steady. It allows for water circulation through the block at all times including during cold-start and idle to avoid hot-spots and air pockets. It also alleviates the situation where often times when running crossovers with bypasses, the t-stat won't open up due to the raw water dumping on top of the t-stat via the bypass which artificially keeps it cool. It takes a little longer to get up to temp, but I can maintain 150* right on the money.

Good stuff. I have crossovers, but no bypass. Seems to work fine with no t-stats in mine. My water temps are a constant 125 and my oil temps are right at 220 during normal running. The oil temps never go over 240 when running the snot out of it and the water temps stay at 125.

Scarab KV
05-05-2009, 09:25 AM
I think mine were drilled also.

boomer35
05-05-2009, 09:28 AM
i've got 3 little drill holes in each of my t-stats. good for airpockets, start ups, and idling.

Tony
05-05-2009, 10:38 AM
Both sets of my engines have had drilled Tstats. This actually allows me to pump my engines full of antifreeze (after draining the cooling system) without having to start them and wait for the T stats to open.

niceguy
05-05-2009, 05:37 PM
Does anyone have a pic of this done to a t-stat they can post. I know it's silly, but I want to make sure I do it in the right spot. LOL

cigdaze
05-06-2009, 08:26 AM
Here you go, niceguy.

niceguy
05-06-2009, 09:24 AM
Thanks CigDaze!!

Chris
05-06-2009, 09:38 AM
I learned this trick from the jet boat guys 25 years ago. If you route your raw water through your exhaust manifolds first, then into your engine, you pre-warm it. Then all you do is put a drilled thermostat in and you have a bulletproof cooling system that never runs cold. On this setup, the engine outlet water runs to your exhaust tails.

MOBILEMERCMAN
05-06-2009, 10:44 AM
The old Mercruisers in the 70's and early 80's were like that as well.

OldSchool
05-06-2009, 11:29 AM
I learned this trick from the jet boat guys 25 years ago. If you route your raw water through your exhaust manifolds first, then into your engine, you pre-warm it. Then all you do is put a drilled thermostat in and you have a bulletproof cooling system that never runs cold. On this setup, the engine outlet water runs to your exhaust tails.

(In my best Guiness beer commercial voice) BRILLIANT!!!

Warlock28SXT
05-06-2009, 01:27 PM
I can't imagine not running thermostats up here in Lake Michigan. The water right now is a balmy 44 degrees.I'm afraid the computers on the Empress would think due to temp it was running too rich and keep leaning until it puked.....

I've got no t-stat per say. It's a restricter washer, T-stat with no guts in it. Had to for Michigan, other wise it would stay in cold start mode and run fat. Temp stays about 125-130* I run a oil stat as well.

jdub
05-06-2009, 08:37 PM
I learned this trick from the jet boat guys 25 years ago. If you route your raw water through your exhaust manifolds first, then into your engine, you pre-warm it. Then all you do is put a drilled thermostat in and you have a bulletproof cooling system that never runs cold. On this setup, the engine outlet water runs to your exhaust tails.

I like that idea. Could you route it like this (1) bottom of one manifold traveling to the top (2) jump across the motor to the top of the other manifold traveling down (3) enter the engine via crossover (4) finally exiting thermo housing with a feed to each tailpipe. What do you think?

Chris
05-06-2009, 11:01 PM
Probably not enough flow for anything with big horsepower. Under 400 hp, most likely no problem. You're still going to have to tee it somewhere to put water into the engine. Why not do it before the manifolds?

jdub
05-07-2009, 07:10 AM
I was thinking you go straight from the water pickup, to the raw water pump, through one manifold, jump to the other manifold, then into the crossover and finally out the tailpipes via thermo housing. Basically a single line from the water pickup to the engine and only splitting at the thermo housing to go to each tailpipe. Or maybe I'm just thinking to much again....:ack2:

Chris
05-07-2009, 08:13 AM
I'm concerned that you're not going to move enough cooling water through one 3/4" hose to cool the engines at max power output. Especially now that you're double-preheating the water through two manifolds. If it got hot enough, you'd be pumping steam into the block, not water.

If you split the lines after your oil cooler, then run in series to each manifold, then to the front of the block, you eliminate the crossover. They split at the water neck on the manifold.

jdub
05-07-2009, 08:10 PM
gotcha ya...

MacGyver
05-09-2009, 12:19 PM
Dumb question, but do you need any RTV on the bolts of the stat cover?

Tony
05-10-2009, 08:52 AM
Dumb question, but do you need any RTV on the bolts of the stat cover?

I've never used any type of sealer on bolts or gaskets on the T stat housings. Never had a leaking issue either.