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79cord
08-16-2007, 03:49 PM
Missadventures with my '79 Accord yesterday!
All ready to go to work but the 'cord wasn't up for it & refused to start so eventually I called work to say I wouldn't be in so I could sort it out...

Battery out to recharge.

Took a look at the distributor & found the stator base cracked which allowed it to move so that the 'contact' peaks on the central shaft collided with it when spinning, smashing those off !
BIG gap for sparks to jump!

Took a look at the '81 Prelude Auto Distributor I have lying around from my '81 Prelude project toy to see if I could raid parts from it but they didn't look interchangeable (5-spd here had vacuum advance but Auto's had dual diaphram for retard as well {?}).
So I raided the (5-spd) project car itself... & swapped that distributor in.
[Geez the '81 TEC distributor cap is annoying; has to be bolted on instead of just clipped on like the '79-80 Hitachi units, which means you almost need to remove the air-cleaner for access!]

Still not starting!

Go mad checking & re-checking timing.

Still not starting!

Remove valve-cover to remove timing belt cover just to re-re-check I haven't mucked thinks up & got things 180deg. out.

Still not starting!

Then notice fuel not getting through. Come to think about it haven't heard fuel pump either.

Now I've been having an intermittent problem for the last month maybe once a week or fortnight, of the engine suddenly loosing power while cruising & stopping, engine often still warming up. Restart the car & it's as though nothing has has happened.
Even found I could put the ignition switch back to the accesories & return to 'ignition' position while still coasting & the engine would immediately be back in action! So I was already suspicious of my fuel cut-off relay (supplies power to pump only when ignition on & power from distributor). And when my fuel pump began to die it would simply refuse to start (although a belting from a tool would normally jolt it into action), rather than stopping once in action.
Come to think of it painfull & drawnout experiance of my CR-X' s relay failing was also intermittent although that also involved failure to pump when starting occasionally.

Raided the remains of my Prelude parts car for its relay (-clipped to back of fuse-box instead of bolted to underside of plenum behind instrument cluster like early Accord) though that one didn't look too healthy either & surprisingly only had 3-pins, without a 4th 'earth pin' like the Accord.

Put a test light aukwardly accross the black/yellow power2pump pins in the connector, (One of those jobs that almost needs 3 hands & a mouth to hold the torch while you lie under the dash) no power.

Fuse in fuse box burnt out! (Even more suspicious of relay)
Replace & Power!

Refit relay & car starts!

Finally!

Though I still don't trust the relay not to short to it's earth again so I've removed it & by-passed it with a piece of wire in the connector for the time being.

Anyone know where I should get a new relay from, If there's anything special about them or if the they really NEED the 4th 'earth' pin ?

Tried one auto parts supplier who had no listing for such an item for the Accord, though I might yet take it down to them & look at what relays they can get for me to try.

Reluctant to bother with HONDA for such a generic part after being quoted $50 for a flasher can several years ago which only differed from $5 standard generic equivalents by the orientation of its connector pins! (Guess the use/design of such things wasn't standardized back then)

Still have to sort out parts to repair distributor as well or grab another from wreakers, pref. '79-80 so electronic ignition but can unclip cap easily!
Still have to replace clutch (original) & probably (hopefully) valve seals & due for oil change as well; having just reached it's 250,000 km birthday.

2ndGenGuy
08-17-2007, 08:36 AM
I'm not sure how generic the fuel pump relay is on these cars, but if it's a 4-pin relay, I'd bet that a $1.99 generic relay would work. A basic relay must have at least 4-pins.

1 ground, 1 signal-pin to trip the relay, and your two wires for what you're switching, one goes from a power source, and the other goes to whatever you're powering...

The relay itself does need a ground... I would check out the wiring to that relay and see if it's configured the same. If so, you should be good to go with the square generic relay...

George
08-18-2007, 05:18 PM
Hi 79cord
I'm new to this forum or anyother forum for that matter of fact so I'm still trying to work me way thru'.
re fuel pump relay. This is a solid state relay which detects pulses from your ignition coil -ve terminal which then turns on the relay. While the pulses are present the fuel pump will be on. Unfortunately its a special relay which will have to be sourced from Honda or the wreckers. Leaving the earth off the relay means the electronics in the relay has no earth reference (ie the electronics inside the relay is floating). Although this may work its unreliable and will cause you some problems in the future. A way around this relay (if you can't find a replacement) would be to use a standard relay wired up so that when the ignition is on the pump is on.
The other problem I think you may also have is the pump itself. You mentioned in your post that a belting on the pump would get it going again. I too have had this problem in the past. The pump has a set of contactors in the back of the unit (under the black plastic cover). When the points are worn the pump starts to fail. They need to be replaced. I replaced mine at ~290,000km with one I found at the wreckers some years ago and have not had a problem with my pump since. Hope this helps.

79cord
08-19-2007, 02:22 PM
Thanks for the feedback,
Still haven't checked Honda for a price on the relay yet, just the local car parts store for a generic fuel-pump relay, many of which are apparently similar & around $12-15, though they didn't have any in stock. So I'm still intending to check with Honda but wanted to get a base figure in case they were completely out of the ball-park.

Seems the relay may not be at fault though since engine die-ing problem still occuring with wire by-passing relay (power supplied through ignition when on, relay belongs there to stop pump if engine stops, ie no fuel due to leak.
Just suspicious of it due to blown fuse & the fact that my last fuel pump did not die in this manner.

Obviously I should also be replacing my fuel filter just in case... Got around to looking in the area on the weekend, though not much more, only to discover leaking rear shock absorber! So obviously I have to get my act togeather & give my car some general love & attention all round.

Have some spare 2nd hand struts somewhere or have been offered a worn set of Koni struts to buy I will have to reconsider...or new.

Also checked local cheapy wrecker for replacement distributor poached from my Prelude, though example I found looked to have worn bearings & was '80 & different design from mine so & couldn't raid it for parts.

P.S spotted smoked '84-5 LH corner light to match RH one I have for 2nd gen guy though it had slight crazing cracks deep in the lens (visible from some angles) so left it.

2ndGenGuy
08-19-2007, 10:13 PM
Thanks '79Cord for keeping the lookout on those lights. ClassicGarage.com has new-old-stock Koni's for dirt cheap...

George: Welcome to the site! You're probably one of the first people to post something useful in a first post. If you've got an old Honda, you should post it on the site, we'd love to see it and hear about it!

Ichiban
08-20-2007, 08:58 PM
Hi 79cord
I'm new to this forum or anyother forum for that matter of fact so I'm still trying to work me way thru'.
re fuel pump relay. This is a solid state relay which detects pulses from your ignition coil -ve terminal which then turns on the relay. While the pulses are present the fuel pump will be on. Unfortunately its a special relay which will have to be sourced from Honda or the wreckers. Leaving the earth off the relay means the electronics in the relay has no earth reference (ie the electronics inside the relay is floating). Although this may work its unreliable and will cause you some problems in the future. A way around this relay (if you can't find a replacement) would be to use a standard relay wired up so that when the ignition is on the pump is on.
The other problem I think you may also have is the pump itself. You mentioned in your post that a belting on the pump would get it going again. I too have had this problem in the past. The pump has a set of contactors in the back of the unit (under the black plastic cover). When the points are worn the pump starts to fail. They need to be replaced. I replaced mine at ~290,000km with one I found at the wreckers some years ago and have not had a problem with my pump since. Hope this helps.


I remember starting my fuel pump in the '83 by smashing a beer bottle over it in the subway parking lot. It required frequent beatings. Sometimes the rocker for the contacts would fall off completely and would require a quick dissasemble/assemble to make work again.

I would replace the fuel pump.

79cord
08-21-2007, 05:30 PM
Yep, Definately the fuel pump now.
It's started showing the more ( all too) familiar trait of not starting to pump until it's been given a beating.

I've never actually dis-assembled the pumps before to check their contacts... Think I still have my old one to play with & investigate... when it started to misbehave a year or so ago I just swapped in one from my Prelude parts car.