Overheating (Pulley Ratios)

FJCentralcoast

New Member
I have just joined up as I have a new Toy - FJ Series 40 Landcruiser. I am currently ironing out the bugs atm, he's Been neglected a fair bit.

It has been engineered with a 351 Cleveland. It has an overheating problem that I have been trouble shooting, and have come to the thory that its due to ( I think Its called ) overspeed water flow - the Harmonic balancer is twice the size of the water pump pulley.

I have been able to keep him cool by restricting flow. So I am on the hunt for the correct size pulleys for Both. Any feedback would be great, I have seen that 1:1 to 1:1.25 seems to be optimium ratio, but once again please correct me if Im not on the right track.

So I guess my question is does any body have recommendations of the above?

Also once I have this fixed up, I am wondering if there are any volunteers around the central coast who might be interested in introducing me to some local tracks.

Cheers
 

Jarh73

New Member
Got an pictures?

I used to work on Clevelands a lot and the bottom pulley has always been huge.

As long as it has Ford factory pulleys I would not change it.

Have you had the radiator removed pulled apart and rodded?

When is it over heating?

At slow or high speeds?

Is the radiator big enough?

Is the ignition timing ok?

Is the thermostat ok?

Cheers

Justin
 

FJCentralcoast

New Member
Hi Justin,

I first removed the thermostat but then replaced with the 165'F replacemnet
I have tuned the Carby with a mate who is a quite familiar with doing so, cleaned the points (thinking to changing to electric) set the timing, the motor is running really well no pinging heaps of power.

We have installed a WB radiator, it came with a brand new 550 x 500 x 75 thought this might not be big enough so went fopr soemthing bigger.

I have installed 2 x 8 inch fans on the inside of teh radiator and built a Shroud from tin around them - there running in reverse pulling the air through and are really beefy.

It still would over heat at idle slow crawls 110'c and I'm sure it would have kept climbing. Driving around above 60 still would sit on 80 - 85'c

I was thinking it could have been the head gaskets put on the wrong way by now.

Then I sat with the hose running over the radiator to keep the radiator cool and found it sat right on the thermosat 73'c -

Still was lost until I came home and My mate had come up with the idea it was that the water was moving around too quickly, which meant the water cant cool in the radiator.

So he had spent some time playing with restricting the flow of water into the engine (crimping the inlet hose) - By doing so we have been able to have him sit in the drive way for 40 min idling and siting right at the thermosat temp.

Driving around giving a bit of hard time up hills and doing 80 km/h it will sit at 85 but normal driving just cruising around and idling around it sits at 73 - 78'c.

I really appreciate your feed back guys thansk - I just want to get out onto tracks - always wanted FJ
 

Fishigan

New Member
Mate, if you can, put the standard water pump pulley/harmonic balancer set-up on it. AND the standard fan. All of my 351s ran sweet with that set-up. At the very least, you would have eliminated that from the equation.
As for the radiator, the original FJ40 rad would have probably been OK. It cools a 4.2 liter 6 cyl and the cleveland was a 4.9 as well. (the only difference between the 302 and the 351 was the crank and rods). Is the WB radiator a 3 core?
 

ERASER

Member
Have the radiator inlets/outlets been moved on the radiator to suit the engine inlet/outlets ? If so make sure their not above each other on the radiator. Also the thermostate should restrict water flow. Ive had v8 40 series before and cooling them is an issue. You need to go overkill on the radiator and also watch that the top radiator hose doesnt sit higher than the radiator otherwise youll get air pockets. 75 series radiators are pretty big and fit straight in. Also i'd be using the original engine driven fan with an original shroud to suit the radiator.
 

struth

New Member
Mate, if you can, put the standard water pump pulley/harmonic balancer set-up on it. AND the standard fan. All of my 351s ran sweet with that set-up. At the very least, you would have eliminated that from the equation.
As for the radiator, the original FJ40 rad would have probably been OK. It cools a 4.2 liter 6 cyl and the cleveland was a 4.9 as well. (the only difference between the 302 and the 351 was the crank and rods). Is the WB radiator a 3 core?

Just to clear up a point the 302 is a 4.9 litre the 351 is a 5.8 litre which is a 40% engine capacity increase on the 4.2

If restricting the flow rate through the radiator keeps the engine cool then I would agree that water flow rate is the first place to look, as someone else already said it will be well worth ensuring your balancer pulley and pump pulley are standard ratio to one another for a 351.

If they are already correct then I would start looking toward the radiator as the culprit.

Cheers
 

FJCentralcoast

New Member
Hi All,

I am just wondering inrelation to Struths message - what is the standard size of both pulleys for the 351 Cleveland?

Thansk for all the posts - Ihave been able to keep temp at 84 with a more restrictive thermostat - put I believe it still needs to be a bit cooler as giving a hard time it gets bit hot

Thansk

Shane
 

Fishigan

New Member
I'm not sure of the ratios or diameters. What I am sure of is that the 351 and the 302 are exactly the same. Go to a wrecker and check them out.
 
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struth

New Member
They are only the same externally, the 351 has a longer stroke and the same bore diameter, therefore has a larger displacement and will generate more heat.

Cheers
 

Fishigan

New Member
They are only the same externally, the 351 has a longer stroke and the same bore diameter, therefore has a larger displacement and will generate more heat.

Cheers

I was referring to the water pump. The stroke is the only difference to the whole motor. The water pump, timing gear, heads, pistons, valves, manifolds, pullies and everything else are exactly the same. They might generate slightly more heat but not enough for ford to stick a different cooling setup on them.
 

struth

New Member
I was referring to the water pump. The stroke is the only difference to the whole motor. The water pump, timing gear, heads, pistons, valves, manifolds, pullies and everything else are exactly the same. They might generate slightly more heat but not enough for ford to stick a different cooling setup on them.

I take your point, I thought you were some nufty who didn't know they are different engines. My apologies:D
 

FJCentralcoast

New Member
Hi guys,
I be been busy and thought I would get back to you all about the overheating prob I was having.
Guess what back to basics and of coarse it's fixed.... A 16 inch fan either side of radiator increased thermostats temp as well as using a hi flow and away we went.....
So sorry about the late post but been playing and been impressed so far. Thanks for all yr feedback this has been the most helpful sight and the only one I am actively using thanks.
I just spent some time traveling to 1770 with camper trailer anyone going that way call n to workmanship beach 6 bucks a night it's awesome.... I would also recommend bald rock same price with hot showers
 
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