Technical Ford Rebluilt 390 overheating / vaporlock?!?!?!?

Have you confirmed the pusher fan is not running the wrong direction? It happened to me once with an electric fan. I had the car running, the fan came on and I happened to walk in front of the car and felt it blowing. I had the motor running backward.

 

That shroud is doing you more harm than good for stationary cooling. For a mechanical fan to pull the best air it needs to be half in the shroud and half out.

 

And Pat was correct when he mentioned only the lower hose needs the wire. The upper is under pressure, and won't collapse.

Jon.

 

This was my first thought also.

 

I agree about the fan shroud being to long. I had a tractor that would not stay cool went to a thicker radiator . Which moved the shroud back still heated shortened the shroud problem went away. Most fans don't like to run backwards if the blades are curved they are very inefficient running backwards.

 

I'll break it down like this; It cools fine running down the road but not standing at idle.
Three things are different going down the road. Air is being forced through the radiator, the engine is running faster than at idle and the throttle plate is open.

The throttle plate position should determine the amount of vacuum on the distributor advance and engine speed determines mechanical advance.

If you rev the engine while sitting still, will it cool? If it does, it could be a timing problem at idle or fan/water pump speed. A smaller pump pulley might help.

If not, the fan shroud might not be working as has been said.

I do the cheap and easy things first. Try running it with the hood open. Maybe the heat is getting trapped under the hood. Driving it helps drag air out from under the car.

Then I'd play with the timing as it's easy and cheap to move.

If you have a shop fan you could try putting that in front of the car to confirm that it's air volume.

Can you use fan spacers to back the fan to the edge of the shroud?

 

- yep - since you have an aftermarket radiator search eBay for aluminum fan shroud with electric fan - that way you can get rid of the monster shroud & pusher fan on front of radiator

 

OK so here's my update.

I pulled my trans lines off radiator and fabed up brackets and installed a nice stacked plate 25 row trans cooler in front of radiator so it's an independent system now. And eliminated the pusher fan ( it was wired as a pusher)

Pulled off shroud

Tmr night I'm going to cut 3" off shroud to put it half in /out of fan blades
install a new high flow water pump and top off coolant with "super coolant attitive"

Thursday my fan clutch and fan come in so they will go on as well as the FUEL INJECTION! Pretty excited about that.

To answer a few questions I already have the matching shroud for the radiator it was for the ele fan. I modified it to work with the bigger upper shroud. it alone was meant for ele fan only and wasn't close to working mechanical fan.

I'm already "overdriving" my fan pully so an even smaller pully mite hurt me.

 

I'll also play with timing more Thursday and maybe vacuume advance canister

 

I had 2 Fords like that, one a 390 and COM and the other was a 352 and manual. Take a quick look at the water pump bypass hose, make sure that's not kinked. The one with the 352 liked no thermostat in warmer months. But both cars really had no terrible cooling issues in the summer months.

 

In my opinion, you are changing too many things at the same time. At that rate, you will never know what your original problem(s) was/were. Also, with the independent trans cooler in front of the radiator, you have not really removed the trans heat 'load' from the radiator. The trans cooler will warm the air passing through it and, at the same time inhibit to some degree, the air flow through the radiator behind it.

You could have simply corrected the fan shroud and removed the pusher fan and tried it that way. If that wasn't enough improvement, go to the next step.....etc.

Your car, you choice in manner of chasing the problem....

Ray

 

Also, It might be a good idea to wait to cut the shroud until you get the new fan and clutch. They might end up either further in or out.

 

Update.
New high flow waterpump installed
New 25 row stacked plate trans cooler installed
New fan and clutch installed
Cut shroud

Had to get edelbrock efi sump kit because fitechs was back ordered till Sept. But that and fitech are both installed and I had it running.

I did the paper check and it's pulling enough air to hold a piece of paper on both radiator and trans cooler at idle

When I cut the shroud I cut 3" off and stopped the fan is still not half in/half out though. I would have to cut another 1" off and by that time the shroud would only be an inch wide I think defeating the purpose of a shroud??

I'll post new pictures in a little bit. Also I'll take new measurements of fan spacing from radiator.
I have a few wiring issues to tidy up with efi.

 

I think you should close enough with the shroud.

 

Also threw on a new k&n. I couldn't put a new efi kit with a old paper filter. Lol

 

Do you have any updates on your progress? Just curious.

 

Good idea.
Update.
I took it for it's first drive and it gets to temp fine and stays around 190 while driving just like before.
If you let it sit it will still creep up and yesterday I let it sit for a few mins and it went right to 205 and I just got impatient and shut it down knowing what the outcome would be.


And she definitely still runs hot. You can feel the hood , fenders everything up front is screaming by they time it says 200degs.

The fi system came with electric coolant temp sensor so I'm very confident that it's accurate and it's reading close to what it was with cheap sunpro gauge

I'm not sure if cutting the shroud helped or hurt. To me it doesn't feel like its pulling as much air now but it still holds paper to radiator at idle.

I reset timing at 12 degs initial at 2000rpm with vacuum plugged off. And when I plugged in vacuum to me it seem that something wasn't 100% right. Still was at 12 degs at idle but the advance was slow to come on and wasn't working right (cheap China hei)

WHATS NEXT.
I sucked it up and ordered a Msd Pro billet distribtuor, Msd blaster 2 coil and holder.
I plan to lock out the distributor 100% and control all timing off my handheld controller. That way I can set timing at idle and when and where I want the timing all through the rpm range.

Also looking into a becool / Griffin radiators to see if there any different than my champion.

Looking into making or having a fab shop make a complete 100% shroud

Or drive the car to a bad neighborhood and light it on fire

 

I've had a few of these (FE's) and one common problem (since they only have 10 head bolts per side) is head gaskets leaking exhaust from the the combustion chamber into the water jacket. Also FE's are often easy to overbore, due to core shift, which can cause hot spots. Good luck!

 

Thanks for the update. I feel your frustration and rightfully so!

I am not comfortable with your initial timing. I always plug off the vacuum advance and idle a vehicle at 600 or so rpms when setting initial. I believe my 60 Thunderbird shop manual calls for 3 degrees btdc at around 600 rpms.

Do you think that setting your initial timing at 1200 rpms is throwing your overall timing off?

Some guys don't worry about initial and get the engine rpms to 3500 rpms and set the total (36 degrees).

 

Agreed. For example, when you make three changes at once there's a real chance that one change will make an improvement and the other two will make matters worse. You'll never know which change made things better. You may not even know that anything did make an improvement.

I'm a little puzzled and disturbed by this statement. Initial timing is not set at 2000 RPM. Initial timing is set at idle speeds with the vacuum advance disconnected and at RPMs lower than when the mechanical advance begins working. And there's two different ways the vacuum advance can be connected. One vacuum source is full manifold vacuum which should be 16 to 19 inches at idle and works well on a lot of street driven set-ups. The other vacuum source is "ported" or "timed" vacuum which is zero at idle and then begins to act like manifold vacuum when the throttle is opened.

I'm not going to begin to guess which is best in your situation. But if it were me I'd start with setting the original stock, true, initial timing with the vacuum advance disconnected then reconnect the vacuum advance to a full manifold vacuum source. But you need to know that the mechanical and vacuum advances are working properly in, well, advance.

 

Ok. So to put an end to all the timing issues I sucked it up and switched to Msd Pro billet and blaster 2 coil.

Now I know exactly what timing is at all times. Initial is at 10deg ,idle is also at 10degs and 36 all in.

Initial is only used for crank then once fired it gos to idle timing.

And with all the changes made it does run about 10degs cooler while cruising 180ish now

BUT it still gets hot while sitting. I haven't let it go past 210 not because that's to hot but because I know it won't stop climbing.

It won't vapor lock anymore but if it's at 205 or 210 when I shut it down it will boil out.

 

Also I called the speed shop and there stuck on an airflow problem at idle. They seem to think if it was overbored or had headgasket issues it would overheat while driving as well as sitting still...

Soo I have no clue.

I'm going to just drive the shit out of it till winter then make a new shroud and hope for the best. Maybe take timing down to 6 or so at idle and see if that does anything.

I know while running it hate anything under 10 with that hei so maybe the msd will change that

 

How about that! Sorry to hear about all the issues you've been having, however, you're not alone. Mine is .060 over, and does not like to run hot (but gets hotter than hell real quick). I'll have post some pictures of the fan & radiator I have, but here is the 390 I've been working with.



-Gets terrible vapor lock (boils out as soon as I park it!)
-Gets hot quickly/does not like sitting in traffic.
-If I sit at a light for too long I have to put it in neutral and keep the RPM's alive with the gas pedal.
-Has a bunch of other problems that are probably affecting it (I think it is the intake manifold gasket...)
It is a total rat rod and I drive it anyways because it makes me happy

My radiator is meant for a 1968 428 and the fan is here: http://www.jegs.com/i/Derale/259/16833/10002/-1?parentProductId=961386 however, I think my fan is drawing too many amps for the stock alternator (the car idles better with the fan off until it is above 190).

 

The msd distributor helped quite a bit.

Still gets hot when it sits in traffic or lines at car shows and it's super hot and humid out. I just drove the shit out of it and stopped worrying. The vapor locking subsided as long as it wasn't 210 degs.

I'm running a fan clutch now and my half ass shroud.

I'm still planning on making a nice custom shroud for it this winter. But I pretty confident that it all stems back to having thin cylinder walls.

 

First thing I'd do with an FE that heats is pull the heads and look for a head gasket in backwards. Or, borrow an infrared thermometer and see if the back cylinders are running too hot because the coolant is just circulating through the front of the engine.

 

That shroud is still a problem! The fan should ALWAYS be set so that it is about 1/2 the blade width into the edge of the shroud. I am sure this is a big part of your problem.
The 416" FE in my 75 F-100 (390 .030" over with a 428 crank) does not get over 180° on 100+ degree days with NO shroud. Your situation is actually damming up the air within the shroud and is worse than None.
Seriously, cut that thing back some more!

 

I checked the headgaskets are on correctly

If coolant is just circulating through the front what would be the cause of that?

 

Yes I do agree the shroud is playing a part in it. She is in hibernation for the winter. I do plan on making a complete new shroud for her this winter!