Some Gt-40 engine questions

Yes, that is the low pressure pump. There is a strainer inside of it, but not a true filter. The filter is inside the FCC. The strainer can clog up. No, the canister on the pump does not unscrew. You have to take the pump off the engine, remove the hoses and 3 small nuts at the top. Those nuts are on double-ended bolts, so you have to reach under the bracket with a thin 7/16" wrench and hold them while removing the nuts.

The sensor you asked about is a cooling temperature warning switch. Somewhere there should be a green wire that also goes to a similar switch near the oil pressure sender. The switches work in parallel, in other words if either switch closes, the red light on the dashboard should come on. The temperature switches had a high failure rate, and also were set at a temperature pretty close to the normal operating temperature. Some previous owner probably took the wire off of it.

TFI is the ignition module.

Art

By the way my GT40 doesn't have that little fuel hose that's referenced as sometimes cracking. Is that hose somewhere else?

Ken, that's awesome you got it fixed. What was the original issue again?

Ken, the brass fitting in the elbow is the anti siphon valve. It has been known to collect debris and cause fuel supply problems. There are 3 fuel lines on the tank the supply line, return fuel line and the tank vent. The other line in the picture is the return fuel line. Ken there is no pressure on these lines. It is the low pressure side anyway. It is only after the FCC that you have the high pressure 40psi.

Ken hope that ankle is going to be ready for your approaching summer season.

Wow, I had to refresh this thread. Very impressive!

Skidim has both the gauge sender and the SLOW temp switch.

Last week I was trying to get the TFI module locally. I found that the EF-EL 5 litre Ford Falcons used the EEC1V but they only used a distributor mount TFI not the remote mount like on the PCM GT40. The AU Falcon also had the 5 litre Windsor motor but they went to separate coil packs on that model. I ended up ordering a TFI unit from Amazon they have good shipping rates Internationally.

You could try your local Ford dealer and see if they can look up a temperature switch in their documentation for these local model Falcons. I would test the gauge on the water pump sender currently in your engine before I ordered one.

You are after the SLOW switch more than a sender. As the sender mounted where the slow switch is works any way although it may be a different NPT size. Skidim indicates the gauge sender on the circulation pump is 3/8" NPT and the SLOW switch is 1/2" NPT. Check for any Ford part numbers on yours or any other part numbers that may help identify them.

*****EDIT since you don't have the SLOW switch it will be hard to check for any part numbers on that. If I get a chance tomorrow I will check my SLOW temp switch for a part number.

Steve,

Now for a couple of questions.

What is the history of your boat imported recently or been in the country for a while?
Do you know if the SLOW circuit was disabled in the recent rebuild?
Did you do the rebuild and put the motor back in?

I would hook up the temperature gauge wire to the sensor on the water pump that is currently not connected and see if the gauge functions correctly. If it does I think the SLOW temp switch has been replaced by a gauge sender. The difference between a gauge sender and a switch is that the gauge sender resistance will change as the temperature changes with a switch it should go from high resistance to short at around 200F fairly quickly.
Have a good look around the wiring loom and see if the tan wire with black tracer possibly still inside the shielding has been tied back somewhere.
You are welcome to bring it down to Tamworth or maybe we could meet at Grafton. I have a mate going to Grafton for the ski racing this weekend.

Steve just to clarify does you temperature gauge function correctly?

i.e. Does the gauge rise to 160F as the engine warms and then drop down when the engine cools.

Not certain if the gauge sender and SLOW switch have been swapped after looking at mine they look the same and appear to be in correct position.

****Also updated earlier ACT ECT location with picture*****

This picture from gun-driver shows the oil pressure gauge sender and the SLOW oil switch clearly. Bottom right hand corner the blue wire is going to the oil pressure gauge sender the other wire with the shielding is going to the SLOW oil pressure switch.



This is a close up of my SLOW temperature switch with the shielding pulled back


The SLOW oil switch with shielding pulled back.

Steve,
The ECT (Engine Coolant Temperature) is located in the inlet manifold towards the front of engine port side not far from the Air Charge Temperature (ACT)sensor. It is a 2 wire sensor that the ECU(computer) uses to modify spark advance and air/fuel ratio.



The SLOW system may have been disabled because one of the sensor(switches) were faulty. They have also swapped the locations of your temperature gauge sensor and the SLOW temperature switch. You will probably need to switch them back to get the wiring loom to fit correctly.

Firstly I would meter the SLOW temp switch and the SLOW oil switch to make sure they are not faulty (with the engine running). They should be either open circuit or a very high resistance when looking for a resistance ohm reading to ground on the engine. If they are not that shows they are faulty and will require replacement.

The SLOW temp switch should have the green wire that goes back to the dash and the tan wire with black tracer connected to its single terminal(as shown on gun-drivers picture). The oil pressure SLOW switch will just have the single tan wire with black tracer.

I doubt if he cut the wire in the loom that gets back to the computer. Having them disconnected is just like the signal from the switch when they are working correctly i.e. not until the temp switch activates (over 200F) or the oil switch (below 5 psi) that the ground signal gets back to the ECU pin 24.

Lewy,

I have looked over the wiring last night and it seems to me and I am not expert on the electrical wiring of this engine that things are not what they should be. I have had the engine rebuilt about 9 months ago, but I have not had it running other than on the hose in the driveway as I have been restoring the boat. The engine runs fine on the hose and the temp gauge and oil pressure gauge works on the dash. I am concerned that someone along the way has bypassed the Limp mode system in my engine, maybe due to problems I am not sure.
What i have noticed is that the SLOW temp switch has only one tan wire(no black tracer) attched to it, the green wire that you mentioned is there but not connected to anything. I chased back both wires to the dash, Tan wire goes direct to the temp gauge, green wire goes to the check engine light. Please see below picture of the SLOW temp switch wiring:


The green wire connects to a darker green wire that when chased back goes to the check engine light please see below picture:



The temp sender has no wire to it at all, see below picture:



I have found, i think a tan coloured wire coming out of the harness that has been cut before it meets the engine see below picture:



I also checked what i believe to be the oile pressure switch, this had a blue wire that ran back to the oil pressure guage in the dash, the other tan wire with black tracer coming from it does not run anywhere it has been taped off.

It seems to me that the SLOW mode system has been bypassed in my engine, not sure why but I would like to have this safety feature operational before I go away with the boat in about five weeks, what are you suggestions guys? Should I just take this to a electrical tech who knows these systems, may be hard to find in Australia, I could try my local dealer but that may hurt the hip pocket. Any suggestions would be an amazing help thankyou

Steve

Just to clarify wiring colours. The slow sensor wire is tan with a black tracer. The wire to temperature gauge sender is a lighter tan without the black tracer.

Steve the days are warming up 25C-28C but the nights are still down in the single digit C's. The water temp is being held back by these lower overnight temps.

Lewy,

Thanks again, I will chase both these issues up. How is Tamworth? is it warming up down there yet?

Steve

Lewy,

Thanks for the reply mate. Ok do you know how to clean the screen in the LP pump?

The temp guage does work, I have not had it in the water in a year as I have been restoring it, but will be getting it wet in a few weeks. Before I pulled it apart and had the motor rebuilt the temp guage did work, is it possible to work without that temp guage sender attached? I would not think so right? So should I be looking for a part of the harness that is not attached? Sorry for the newbie questions, but like I said the engines I am learning about. Hope this makes sense.

Let me know what I should look for please Lewy.

Steve

Guys,

I have some parts I just need some confirmation with please bear with me as I am familiar with most things on the boat however I am learning with the engine. I wish I had Lewy`s knowledge on these engines. By the way I have the 5.8L gt-40 engine with the FCC in a 1997 Sport

In the picture below is this the low pressure fuel pump?



My next question is does this pump have a filter inside? I am trying to source the filter and means of accessing the filter if there is one in this pump please see next picture below



My next question is I identified a sensor I believe on the front of the engine that does not have any connections to it can anyone identify this for me please, see below picture



Here is another picture of a close up of the sensor, see picture below



Any help would be great, Lewy or anyone I hope you can help me out here, just want this boat to run fault free all summer.If there is a filter for the low pressure pump is it available from Nautiqueparts? Or Lewy can I source it here in Australia? All this talk about TFI modules has me worried. I have ordered the code reader that Lewy has suggested on other threads. Sorry if this has been addressed somewhere here before. Thanks again guys.

Steve