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stu cordova (Balataboy)
Posted on Tuesday, August 28, 2001 - 9:57 am:   

OK guys, now I'm confused. It seems the advice is to either add busbar, or replace, the fuse panel to fix the problem. However on my QV the fuse panel and the relay panel are two different panels (is this different from other models?). The relay panel is the one heating up, the fuse panel is fine. So are you actually suggesting I replace, or add busbar (and I don't really know what that is), to the RELAY panel? Thanks!
Herbert Edward Gault (Irfgt)
Posted on Tuesday, August 28, 2001 - 4:29 am:   

If there is a wiring diagram in the owners manual it is simple to trace back the wires from the relay and find where and to what other components that they go to. Something is signaling the relay to de-energize on deceleration.
Nick Scianna (Nick)
Posted on Tuesday, August 28, 2001 - 3:56 am:   

Hi.Magoo's fix idea is a GOOD temporary one.I have given you my opinion via the telephone,I still feel,if its very hot,it is the fuse pannel,that is the"common problem"The relay does not normally click on & off during de acceleration,I am positive it does not on a Euro spec car,[that is what your is if I remember correctly]for any emissions-fuel mileage reasons what so ever.Nick..
magoo (Magoo)
Posted on Monday, August 27, 2001 - 11:22 pm:   

I would think that to take his worry away from the hot relay, regardless if it is normal or not, he could install the buss bar to divert some of the heat and avoid a potential problem in the fuse panel board in the future if it is getting that hot. This way he addresses the entire problem.
Herbert Edward Gault (Irfgt)
Posted on Monday, August 27, 2001 - 5:26 pm:   

I still believe as in my earlier post that the reason the relay cuts out on deceleration is that the fuel is not needed on a coast and to increase mileage and reduce emissions. All modern cars with electronic fuel injection shut off the injectors on a coast condition for this exact reason and I suspect that with the CIS system that this is their way of duplicating mechanically what is done electronicly on newer cars. If your car is running OK then I believe you do not have a problem.
'75 308 GT4 (Peter)
Posted on Monday, August 27, 2001 - 1:38 am:   

On the 5-pin relays that these 308's and other Ferraris use, there is an arm that connects the imput power from pin #30 (+ 12V) to pin #87 (or 87a, or 87b depending on the type of 5-pin relay used). This arm is pulled by the coil (the coil recieving its power through pins #85 & 86, which is from the accessory switch). This coil makes a clicking noise on contact.

Using this explanation, maybe the coil is recieving power intermitedly. Somewhat unlikely.

Although Stu, when looking back at the very beginning of this thread, it reminded me when I still had my car on the road, and coming back from Seattle to Vancouver, driving on a s---ier part of the I-5, I noticed an intermitent clicking noise coming from the relay panel (which, on my GT4, is located by the passenger's side footwell). So bad in fact, that I pulled off the highway on a small road. I poked around there, checking for burnt items, loose stuff. I attributed the noise to a loose fiberglass panel in that area. In my case, smooth road = no noise, bumpy road = creaky, clicky noise. Sometimes and sometimes not. Ahhh the joys of discovering the intricacies of a Ferrari!
stu cordova (Balataboy)
Posted on Sunday, August 26, 2001 - 9:15 pm:   

Herbert - thank you for that! Interesting thought, so.....what do you suspect causes the relay to "click" on decelaration. I guess I can ignore the heating up, but that noise just doesn't seem right or normal. Just ignore it too?
BTW - I checked both the fuse box and back of the relay panel - no hot, discolored or loose wires. All appears to be fine.
Herbert Edward Gault (Irfgt)
Posted on Sunday, August 26, 2001 - 8:42 am:   

Just for an experiment, I took a new fuel pump relay and connected it to a 12 volt battery and energized just the electromagnet portion terminals. In 5 minutes the outside of the relay had a temperature of 117 degrees and the terminals themselves had a temperature of 130 degrees. If you add the load of the fuel pump to the contact points and the normal resistance they produce then there is no reason not to expect the temperature to go much higher and this be a NORMAL condition. I honestly believe you are chasing a non existant problem.
magoo (Magoo)
Posted on Saturday, August 25, 2001 - 9:46 pm:   

Stu, go to KEYWORD and type in Buss bar.
stu cordova (Balataboy)
Posted on Saturday, August 25, 2001 - 9:22 am:   

Update....(sorry this is late - been away)
As some of you suspected, after replacing the fuel pump and the accumulator, I still have a clicking relay (on decelaration only) and it's still heating up to the point of being way too hot to handle. Oh well, nice to know I have a new pump anyway. On to the next possible cure....

QUESTION: In replacing the accumulator, is there supposed to be a hose of some kind attached to the long nipple at the back of it? There wasn't one attached when I took it off, but I'm wondering if there was supposed to be? Or is this just a breather line/tube of some type? Thanks!
Warren E. Smith (Magoo)
Posted on Sunday, August 05, 2001 - 11:56 pm:   

Good Luck Stu, Let us know.
Warren E. Smith (Magoo)
Posted on Sunday, August 05, 2001 - 11:54 pm:   

Stu, Don't forget the fuse panel board. Check for hot spots, where the terminals are loose.
stu cordova (Balataboy)
Posted on Sunday, August 05, 2001 - 11:49 pm:   

Thanks for the input. Magoo - I received my new pump from Nick on Saturday and was going to install today but ran out of time. (Rode just a little too long on my Harley). I've also decided to replace the accumalator (sp?) as well and will need to pick it up tomorrow.
So for now, I don't know if this is going to solve my "hot-clicking" fuel pump relay, I'll keep you posted though. Thanks again all (Monty too) for the help!
Warren E. Smith (Magoo)
Posted on Sunday, August 05, 2001 - 11:06 pm:   

STU, What did you find RE: The hot relay problem?
Herbert Edward Gault (Irfgt)
Posted on Friday, August 03, 2001 - 5:38 am:   

One other thought. Look on the back side of the fuse box where the relay plugs in. Where the wires connect to the relay. If there is excess heat the wire insulation will look discolored and burned around the terminals. If not, drive on.
Herbert Edward Gault (Irfgt)
Posted on Friday, August 03, 2001 - 5:31 am:   

I do not know this for sure but I believe that the reason the relay shuts off during deceleration is for fuel economy and emissions as the pump is not needed during that time. It does not take a lot of heat to burn your fingers so I still believe you are chasing something that may not be there. One way I look for an operating relay on other cars is by feel as to which one is hot. As I understand it you are not having any actual problems with your car. Check the relay connections and if they are OK I would drive on.
Warren E. Smith (Magoo)
Posted on Thursday, August 02, 2001 - 8:30 pm:   

Stu, What Heath is talking about RE: circuit board heating up at the loose terminals is more probable than the pump motor after I remembered all the discussion we have had about the loose terminals and the plastic backing on the board melting. I would definetly check the back of the board to see if the terminals are loose causing a problem. If so there is a section on adding buss bar to the terminals to eliminate some of the heat. Look under keyword in the archives and type in buss bar. You should also bench test the pump to see if it binds, slows down, when it gets hot.
stu cordova (Balataboy)
Posted on Thursday, August 02, 2001 - 6:27 pm:   

Herbert,
I appreciate that thought, - I am aware that replacing the fuel pump may not solve my problem, however I'm not sure what to do next! Short of taking it to the dealer, I just figure that a new pump is the next logical step.

BTW - the relay gets so hot it will burn your fingers! That can't be normal, can it???
Herbert Edward Gault (Irfgt)
Posted on Thursday, August 02, 2001 - 4:45 pm:   

Keep one thing in mind. Relays naturally get pretty warm as a normal condition since they are in essence an electromagnet. You may be chasing a problem that does not exist.
stu cordova (Balataboy)
Posted on Thursday, August 02, 2001 - 11:53 am:   

Thanks again for the advice. I checked and REPLACED all fuses, conectors and relays and I still have a fuel pump relay "click" on deceleration as well the relay gets very hot. Any other suggestions before I replace fuel pump? As Magoo says, it may be binding.

Those of you who have replaced the fuel pump on a 308...any thoughts or suggestions before I start? Looks like a fairly easy job but then I've thought that before only to find myself in over my head. Thanks again
Low Kai Chin (Speeddemon)
Posted on Monday, July 30, 2001 - 2:43 am:   

Magoo is right, the same thing (bad contact) happened to my relay for lights and literally melted the box. The bad contact means that there is less surface-to-surface contact area which forces the electrons to travel over a smaller 'bandwidth' thus causing lots of head. Check all you connectors, fuses etc.
Warren E. Smith (Magoo)
Posted on Sunday, July 29, 2001 - 10:46 pm:   

Very good point Heath, I had forgotten about the terminals getting loose on the old style boards and not making good contact. Very good possibility and more probable.
HEATH VAUGHN (Heath)
Posted on Sunday, July 29, 2001 - 10:01 pm:   

EDWARD SALLA HAD A MOD DONE BY A COMPANY CALLED NORWOOD IN DALLAS. THEY PUT A RELAY AND FUSE IN THE ENGIN COMPARTMENT TO RELIEVE THE HEAT PROBLEM ON THE FUEL PUMP FUSE AND RELAY. MINE CAUSED SO MUCH HEAT I HAD TO REPLACE MY CIRCUT BOARD WITH A NEW UP GRADE. YOU MIGHT CHECK WITH EDWARD FOR MORE INFO. LOOK ON GENERAL DISCUSSION UNDER MONDIALS, 308 ETC. AS I UNDERSTAND, IT IS A COMMON PROBLEM THAT CAN CAUSE YOU A OF OTHER PROBLEMS (THE HEAT WARPPED MY CIRCUT BOARD AND MELTED MY FUSE HOLDER)I HAD TO UPGRADE TO A NEWER CIRCUT BOARD.
Warren E. Smith (Magoo)
Posted on Sunday, July 29, 2001 - 8:30 pm:   

Haven't had the problem Stu but my guess would be that the pump is binding and heating up the windings and armature. Might want to bench test it.
stu cordova (Balataboy)
Posted on Sunday, July 29, 2001 - 8:19 pm:   

I recently began hearing a clicking sound coming from the fuse box/relay area when decelerating my '85 308. When I removed the cover to try and figure out which relay it might be, I noticed the fuel pump relay was very hot. I replaced it, but it still makes a clicking sound and is still heating up. Anybody experience the same or any thoughts?
Thanks in advance. -Stu

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