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Am into engine rebuild, few tweeks here and there will post when done.
but please can i have some info.
there is a frost plug in the thermostat by pass tube. i remember something about this from years ago. was this because there was problems soucing the correct thermostats or for some reason.
can i have relivant information as to the pros and cons of this or should i go back to standard.
I have a new high flow, cleavland waterpump which has the bypass tube.

ok alittle more info.

have checked old forum posts and a brass bypass restrictor is mentioned and shown for sale by Marlin. why the restrictor? the frost plug in my block looks about the size of the hole in the centre of the brass bypass restrictor. this is bassed on photo of restrictor.'
if more info is needed ill get a photo tomorrow.

any help on this is much appreciated. thanks.


cj
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thanks,
have just been trying to load my first picture just now and not having much luck. was of block and bypass.
the post mention addresses the thermastat isue not frost plug in the restrictor hole issue so we are half way there thanks.

just about completed short block build today., crank, pistons, cam and oil pump installed.

you can just see the plug in the bypass here.

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Some people do call it a bypass restrictor.
I don't think its designed to restrict flow as such, its really a brass seat for the thermostat plunger.
Being brass it won't corrode, where as the iron block certainly would have.
When I received my car from the USA it had the same frost plug fitted as yours has, (Americans call them core plugs or Welsh plugs).
Thats not original, for some reason certain people feel the need to block it off & not use the warm up bypass.
Which means your engine would take ages to get warm, not a good thing for oil tempreture etc.

Yes, Marlin does sell the correct brass seat.
You need to get the correct thermostat to suit the Cleveland, (Winsor is different).
You may find it difficult to find in NZ as I found it impossible to find here in Australia.
Crazy when you consider the Cleveland was made here in Australia for a number of years.

When shopping at most parts stores they try & sell you a Windsor part telling you they are all the same.........their not !
Do a search on this Forum & you will find the correct thermostat part number & before you install make sure the plunger will actually cover the hole in the brass seat.
Stant make a thermostat to suit the Cleveland & I'm sure you can purchase these online from Summit or Jegs.

regards,
Tony.
Thanks Edge.

what happens if i use the wrong therostat.
ie the bipass hole is only partially blocked. is the fear that the water will take the route of least resistance and cerulate around the block and avoid the radiator?

i seem to remember the idea for the frost plug in the restrictor came from the forum years ago, funny how no one seems to remember this.
Chris,

The Cleveland was originally designed to use the brass restrictor plate WITHOUT the frost plug, a water pump WITH a bypass passage, AND a CLEVELAND SPECIFIC thermostat.

Others have modified the original Cleveland design by adding a frost plug to the brass restrictor plate (as you have in yours), using a water pump WITHOUT a bypass passage, and using ANY thermostat.

John
The cooling system incorporated into the 351C engine block was quite advanced for its day. Its a high tech system, it operated more intelligently than anything Ford had designed prior to that time.

The thermostat was removed from the intake manifold to allow for better intake manifold runner design. Relocating the coolant crossover from the intake manifold to a lower position in the cylinder block also directed more coolant flow toward the exhaust side of the cylinder head where it is needed most.

The cooling system is a high flow design which utilized a Robertshaw high flow thermostat as original equipment. The cooling system also features an advanced high flow internal warm-up system they called the "Controlled Bypass System". The engineers were able to recirculate a greater amount of coolant during warm-up because they employed the Robertshaw thermostat in a unique way to restrict the recirculation passage when the motor reaches operating temperature.

Upon cold start-up the thermostat is closed, coolant flows through the large diameter bypass hole below the thermostat back into the coolant pump suction, thereby bypassing the radiator, quickly heating the coolant while maintaining a high rate of coolant flow through the block and heads. This allows for faster, more even warm up without hot spots, especially in the area around the valves. When the coolant warms sufficiently the thermostat opens and the bypass hole below the thermostat is restricted by the cup shaped bottom of the thermostat which extends downward and fills the hole.

The new coolant system improved the thermostat's ability to control water temperature with less cycling, and increased flow to the radiator while virtually eliminating recirculation during normal operation. Heater performance was also improved.

You can't improve upon this system, so from my point of view, as long as the correct parts are available why modify it?

John has already mentioned the parts you need:

(1) A water pump with the recirc passage unplugged
(2) The specific 333 series Robertshaw thermostat
(3) The proper recirc plate that installs in the block below the thermostat.

Here's some pictures





One more view of the thermostat



Of course, Aussies & New Zealanders are used to seeing it like this Smiler



The 180 degree Robertshaw thermostat is on back order, but the last time I checked the 192 degree version was still available (from Flow Kooler). The OEM thermostat was actually a 192 degree thermostat so the lack of a 180 degree thermostat is no big deal as far as I'm concerned; but swapping a thermostat with a different temperature rating means you must make sure to use the proper temperature switch for controlling the cooling fans.

There is no reason to use individual temp switches for controlling the cooling fans. I recommend utilizing only one fan switch installed in the lower (i.e. inlet) tank to control both fan relays; this shall cycle the fans off and on simultaneously. Plug the M22 bung in the upper tank with an unused switch or an M22 plug. The ideal switch mounted in the lower tank, for use with a 192°F (89°C) thermostat is an Intermotor #50104 which has settings of 97°/92°. The ideal switch for use with a 180°F (82°C) thermostat will have settings of 90°/85°; however I am not aware of a switch with these settings having M22 threads. Alternative switches having M22 threads but slightly higher settings (92°/87°) are a Wahler #823.959.481.F or an Intermotor #50200.

The proper way to modify the system (yes there is a proper way) so you don't have to rely upon the availability of the 333 series Robertshaw thermostat is to replace the recirc plate below the thermostat with a plate having a smaller 1/4" ID hole, and use the universal series 330 Robertshaw high flow thermostat. The 330 series thermostat does not have an availability issue and using it maintains the high coolant flow design built into the system, the 1/4" hole in the plate below the thermostat allows the engine to still recirc coolant during warm-up. There are 2 draw backs however:

(1) there is always a small amount of coolant recirculating (i.e. bypassing the radiator) even when the motor is at normal operating temperature. This was normal for all of the Ford motors that preceeded the Cleveland, and normal for all other American V8s of that era as far as I can remember.

(2) there is less coolant recirculated during warm up, so temperatures during warm-up are less consistent and there's a greater chance of steam pockets and hot spots forming in the cylnder heads. But this is better than no recirculation of coolant at all.

-G
The only aftermarket water pump built WITHOUT the bypass feature that the stock pump has is the WEIAND aluminum 351c pump.

It can easily be modified to the stock configuration though. I have the Weiand pump and it is modified.

The Edelbrock is in the stock configuration and needs no further attention.

Personally I think there is too much Chevy think going on that caused this?
Thanks for the info, now to locate the thermostat. I have the pump and the brass restrictor.

cheers for your input

quote:
Originally posted by Cowboy from Hell:
The cooling system incorporated into the 351C engine block was quite advanced for its day. Its a high tech system, it operated more intelligently than anything Ford had designed prior to that time.

The thermostat was removed from the intake manifold to allow for better intake manifold runner design. Relocating the coolant crossover from the intake manifold to a lower position in the cylinder block also directed more coolant flow toward the exhaust side of the cylinder head where it is needed most.

The cooling system is a high flow design which utilized a Robertshaw high flow thermostat as original equipment. The cooling system also features an advanced high flow internal warm-up system they called the "Controlled Bypass System". The engineers were able to recirculate a greater amount of coolant during warm-up because they employed the Robertshaw thermostat in a unique way to restrict the recirculation passage when the motor reaches operating temperature.

Upon cold start-up the thermostat is closed, coolant flows through the large diameter bypass hole below the thermostat back into the coolant pump suction, thereby bypassing the radiator, quickly heating the coolant while maintaining a high rate of coolant flow through the block and heads. This allows for faster, more even warm up without hot spots, especially in the area around the valves. When the coolant warms sufficiently the thermostat opens and the bypass hole below the thermostat is restricted by the cup shaped bottom of the thermostat which extends downward and fills the hole.

The new coolant system improved the thermostat's ability to control water temperature with less cycling, and increased flow to the radiator while virtually eliminating recirculation during normal operation. Heater performance was also improved.

You can't improve upon this system, so from my point of view, as long as the correct parts are available why modify it?

John has already mentioned the parts you need:

(1) A water pump with the recirc passage unplugged
(2) The specific 333 series Robertshaw thermostat
(3) The proper recirc plate that installs in the block below the thermostat.

Here's some pictures





One more view of the thermostat



Of course, Aussies & New Zealanders are used to seeing it like this Smiler

yess, also the water will rotate around our engines oposite to the usa as well


The 180 degree Robertshaw thermostat is on back order, but the last time I checked the 192 degree version was still available (from Flow Kooler). The OEM thermostat was actually a 192 degree thermostat so the lack of a 180 degree thermostat is no big deal as far as I'm concerned; but swapping a thermostat with a different temperature rating means you must make sure to use the proper temperature switch for controlling the cooling fans.

There is no reason to use individual temp switches for controlling the cooling fans. I recommend utilizing only one fan switch installed in the lower (i.e. inlet) tank to control both fan relays; this shall cycle the fans off and on simultaneously. Plug the M22 bung in the upper tank with an unused switch or an M22 plug. The ideal switch mounted in the lower tank, for use with a 192°F (89°C) thermostat is an Intermotor #50104 which has settings of 97°/92°. The ideal switch for use with a 180°F (82°C) thermostat will have settings of 90°/85°; however I am not aware of a switch with these settings having M22 threads. Alternative switches having M22 threads but slightly higher settings (92°/87°) are a Wahler #823.959.481.F or an Intermotor #50200.

The proper way to modify the system (yes there is a proper way) so you don't have to rely upon the availability of the 333 series Robertshaw thermostat is to replace the recirc plate below the thermostat with a plate having a smaller 1/4" ID hole, and use the universal series 330 Robertshaw high flow thermostat. The 330 series thermostat does not have an availability issue and using it maintains the high coolant flow design built into the system, the 1/4" hole in the plate below the thermostat allows the engine to still recirc coolant during warm-up. There are 2 draw backs however:

(1) there is always a small amount of coolant recirculating (i.e. bypassing the radiator) even when the motor is at normal operating temperature. This was normal for all of the Ford motors that preceeded the Cleveland, and normal for all other American V8s of that era as far as I can remember.

(2) there is less coolant recirculated during warm up, so temperatures during warm-up are less consistent and there's a greater chance of steam pockets and hot spots forming in the cylnder heads. But this is better than no recirculation of coolant at all.

-G
A question, maybe stupid, but that has never held me back... Can we see a picture of a water pump with and without the recirc passage plugged? I never knew it could be plugged, neither which hole we're talking about. Fortunately my car cools just fine, but if I one day need a new water pump, I want to get the right one.

BTW, it sounds/looks like a genius system, wonder why other manufacturers didn't copy it?
"We" did this mod on my pump this spring. Great results (no more cold-blooded Cleveland!)

There was a little more to it than the link indicates, but nothing a super-hero machinist couldn't fix. (JAD Machine, Mancos, CO)



quote:
Originally posted by jb1490:
Mikael,

Here's a link showing water pumps with and without the bypass, and how to add the bypass to a pump that doesn't have one.

http://pantera.infopop.cc/eve/...880012344#6880012344

John
quote:
Originally posted by Edge:
Some people do call it a bypass restrictor.
I don't think its designed to restrict flow as such, its really a brass seat for the thermostat plunger.
Being brass it won't corrode, where as the iron block certainly would have.
When I received my car from the USA it had the same frost plug fitted as yours has, (Americans call them core plugs or Welsh plugs).
Thats not original, for some reason certain people feel the need to block it off & not use the warm up bypass.
Which means your engine would take ages to get warm, not a good thing for oil tempreture etc.

Yes, Marlin does sell the correct brass seat.
You need to get the correct thermostat to suit the Cleveland, (Winsor is different).
You may find it difficult to find in NZ as I found it impossible to find here in Australia.
Crazy when you consider the Cleveland was made here in Australia for a number of years.

When shopping at most parts stores they try & sell you a Windsor part telling you they are all the same.........their not !
Do a search on this Forum & you will find the correct thermostat part number & before you install make sure the plunger will actually cover the hole in the brass seat.
Stant make a thermostat to suit the Cleveland & I'm sure you can purchase these online from Summit or Jegs.

regards,
Tony.


Tony, how does that brass plate fit in? Is it press fit in? Tap it in? Seems like it would come loose.
Thanks Tony.
I think i have sourced one through Mike Drew.

i have the brass restrictor in place just have to make sure we dont damage it removing the frost plug.
cheers Chris. Where in OZ are you?

quote:
Originally posted by comp2:
quote:
Originally posted by Edge:
Some people do call it a bypass restrictor.
I don't think its designed to restrict flow as such, its really a brass seat for the thermostat plunger.
Being brass it won't corrode, where as the iron block certainly would have.
When I received my car from the USA it had the same frost plug fitted as yours has, (Americans call them core plugs or Welsh plugs).
Thats not original, for some reason certain people feel the need to block it off & not use the warm up bypass.
Which means your engine would take ages to get warm, not a good thing for oil tempreture etc.

Yes, Marlin does sell the correct brass seat.
You need to get the correct thermostat to suit the Cleveland, (Winsor is different).
You may find it difficult to find in NZ as I found it impossible to find here in Australia.
Crazy when you consider the Cleveland was made here in Australia for a number of years.

When shopping at most parts stores they try & sell you a Windsor part telling you they are all the same.........their not !
Do a search on this Forum & you will find the correct thermostat part number & before you install make sure the plunger will actually cover the hole in the brass seat.
Stant make a thermostat to suit the Cleveland & I'm sure you can purchase these online from Summit or Jegs.

regards,
Tony.


Tony, how does that brass plate fit in? Is it press fit in? Tap it in? Seems like it would come loose.
quote:
Originally posted by Edge:
It is a tap in fit.
Would be best to use a piece of Aluminium bar as a drift.
So the bar sits over its total diameter & presses it in evenly.

regards
Tony


My engine is already in the car so it is less then optimal trying to get the brass insert in.

I have a 400 not a Cleveland but it should be the same.

I tapped on it pretty good with a socket but no go. I took a dremel with a barrel sander and made sure the inside surface was clean. I tried again, no go.

I was beginning to wonder if I need it.
Be a good idea then to vernier the port & the brass insert before attempting the job to see what the interference is.
And making sure the hole is free of rust scale & any other debris that has built up over time.
I drifted mine in place whilst the engine was in the car.
Not easy do get to, but certainly not too difficult once the firewall is removed.

regards,
Tony.

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