85 gl1200I fuel pump relay issue

[bassplayer88]

Well I was syncing the carbs on my 85 GL1200I after getting the resurrected main wire harness installed and getting her running for the first time. She ran fine for about an hour, just about had the carbs very close to perfect sync, when she started sputtering and died . I first thought low fuel or clogged filter but added uel , check the filter all good. She had cooled off and I tried it again and it started with the choke on , and the sputtered then died again. cranked over not issues , but no fire. I pulled the plugs , bone dry .. then cracked out the 85 HONDA Electrical Trouble Shooting manual , and followed and tested all the fuel pump steps. Bad/dead fuel pump relay .. Question is, can they still be bought NEW, and where, I can't find a existing part No# for it? .. Looking at the schematics , it just a 3 pin relay, 12v feed, pulse ground from ignition control, and load going to the fuel pump. Has any one used an after market relay, for this issue ?

Thanks

[SIR tricky]

I think the number is 36100-471-701

It can be found on the Ignition coil 1 schematic item 25


Not sure if they are available new, I did get one off a friend and they are available on ebay of course.

Can't see why an after market (electronic) relay can't be used, would be interesting to find out.

[bassplayer88]

Well I bought a standard 5 pin fuel pump relay and wired it instead of using the OEM relay, and it works but it uncovered the real issue. The fuel pump itself.

wiring up a standard relay to replace the OEM relay is basically the following:
1) cut the plug off
2) attach a spice feed from the ignition switch wire attach a blade connector to each
3) attach a blade connector to the pulse ground
4) attach a blade connector to the feed White wire
5) heatshrink the 87a blade pin to insulate
6) ignition switch x2 feed connect ( 1 at 30 1 at 85)
7) feed wire (white) connects to 87
8 ) ground pulse wire connects to 86 .
You can find these at any auto parts store, about $12.00.
I actually used the exact wire colors, taken off my burnt harness as extensions. I used non insulated crimps/ heat shrink.

Real issue .. All trouble shooting based on the Honda Factor manual pointed at the relay, but she the ran fine for a few minutes then acted like it was starving for fuel then die , continued .. I happen to notice when it started to act up that no fuel was passing through the fuel line from the tank, hand on the fuel pump .. no pumping .. I disconnected the fuel pump and removed it . I connect a battery charger to it and it ran just fine. So I connect a couple fuel lines to it and put both feed and outlet lines in a can with clean gas in it. energized the pump and let it run , in just a few minutes the pump locked up ..
So searching on this sight I decided, and have ordered a Airtex E8316 and will install this fuel pump on the GL1200. I think it was neoracer that posted about it , but there was no addition posts on the results .. so we'll see.

Enjoy .

[SIR tricky]

The original relay is electronic where the one you replaced with is mechanical.
Although yes, they are both relay's and do a similar job. the mechanical relay is really designed to be in either ON or OFF configuration. The electrical relay getting it's signal from the IGN coils is continually switching on and off depending on the speed of the engine.
I doubt that the mechanical relay would withstand the constant switching for very long.

I could be wrong.

The safety issue between the switching relay and the older method of having the pump energized by the IGN switch is, if the engine is not running the pump is no longer pumping gas, the older method would have the pump pumping gas if the engine is not running but the IGN is still ON. In an accident this combination could be deadly.

Remember when we switched the IGN on and then we would hear the pump ticking away in today's vehicles this is no longer the case.

[bassplayer88]

The original relay is electronic where the one you replaced with is mechanical.
Although yes, they are both relay's and do a similar job. the mechanical relay is really designed to be in either ON or OFF configuration. The electrical relay getting it's signal from the IGN coils is continually switching on and off depending on the speed of the engine.
I doubt that the mechanical relay would withstand the constant switching for very long.

I could be wrong.

The safety issue between the switching relay and the older method of having the pump energized by the IGN switch is, if the engine is not running the pump is no longer pumping gas, the older method would have the pump pumping gas if the engine is not running but the IGN is still ON. In an accident this combination could be deadly.

Remember when we switched the IGN on and then we would hear the pump ticking away in today's vehicles this is no longer the case.

I didn't change any of the source wiring, It acts exactly like the original. When I say ignition switch , the actual name as per Honda is Ignition Control switch . If the engine isn't running the pump isn't energized, the safety control in the OEM design and this one is the Pulse Ground.
If you look at the schematic of the OEM relay in the Honda Electrical Trouble Shooting Manual it doesn't show it as electronic, yes its epoxy encased 80's version of weatherproofing. It still has a inductor, creating a magnetic field to close/open the switch (mechanical), it doesn't show using I/C's to switch power feed from one leg to another. The OEM schematic shows that it is using an internal feed from the the Ignition Control Switch wire 12+ connector to energize the Pos side of the inductor, and the source feed. The Ground pulse closes the switch.
Yes the relay I'm using is a on/off constant design, this may come into play at low rpm's like idle 1000rpm, give 1 pulse per rev, it would have a open switch every .06 seconds, 3000 rpm .02 seconds, 4000rpm .015 seconds. If its x2 multiplier, which is possible given their are x2 pulse generator sensors , idle 1000rpm = .03 sec , 1500rpm = .02 seconds, 2000rpm = .015 sec, 3000rpm = .01sec 3500rpm = .008 sec. Based on the reaction time of the relay de-energized inductor and the mechanical switch open time( unknown), I guessing any RPM's above 2000 will act as a constant, with the pulses coming faster than the mechanical switch can react..

[SIR tricky]

I did dissect the original when mine died and I did consider the option you did, I did not find any mechanical switch.
I did consider an aftermarket electronic switch but when looking at the $80 price range I went for a used one for $20. I do carry a spare.

Like I said in the post "I could be wrong"

It will be interesting to see how long yours lasts.

Keep us posted, lets face it if it works it is a cheaper fix, you can pick those relays up for a .50 cents at the wreckers

[bassplayer88]

After posting , I thought it is possible the Honda Technical writers just put a basic representation relay schematic in the manual due to Honda Tech's aren't Electronic Engineers, keep in mind most Service manuals are written on a 6th grade reading level .. We'll see how it works, if not so good, the original plug can easily be put back on . I really would like to migrate away from all the OEM relays, either by redesign or straight replacement, to easily purchased ones and relocate all to the fairing cavity for easy access.

[bassplayer88]

Well here's an update ,

I got her running smooth again .. ... I installed the airtex e8316, with the relay mod. She still acted as if she was starving. So pulled off the relay put back on the OEM, and noticed the white feed wire was a little frayed. Cleaned it up , installed the OEM relay and she fire right up and ran smooth. I synced the carbs and did a slow accelerate test and all 4 stayed matched on the carb sync up to 5k , didn't take her any higher while on the sync.
So since had her running well, I tried to reproduce the problem. I connected the standard after market relay, and it is triggering, but I believe not fast enough to keep up. So I would chalk the after market relay up as a failure and not a replacement. How every, the aftermarket fuel pump Airtex e8316 ( bought at Advanced), works great. The Airtex does have a little bit more noise than the OEM fuel pump, if you listen close you can hear it pumping, verses the OEM which was noiseless. It also sits a little farther out, but I'm going to make mount for it so it seats closer into the engine space, so a fuel pump cover will work.
I'm tempted to put the OEM pump back on to see it it still acts up just get the actual root cause. So far its a harness white wire fray and a bad fuel pump, but for now I'll just enjoy letting her run ...
Hope this helps someone out ...

[SIR tricky]

Thanks for the follow up.