Fuel pump no power/ relay to pump help

[bruceb58]

I just looked at the picture of the relay in the first picture. That relay has a diode across the coil which the original Volvo relay does not have and doesn't need.

Since the Volvo relay is wired with pin 86 to ground, the diode inside the relay is going to pop.

What happened to the socket that the original relay used to plug into?

 

[bruceb58]

The one circuit breaker is on the red wire going to pin 30.

There are no other breakers. Which manual are you looking at? I am looking at the OEM Volvo manual for LK series.

What is your full model number?

 

[flyhigh123]

I just looked at the picture of the relay in the first picture. That relay has a diode across the coil which the original Volvo relay does not have and doesn't need.

Since the Volvo relay is wired with pin 86 to ground, the diode inside the relay is going to pop.

What happened to the socket that the original relay used to plug into?

I have the socket. but what happened was all the wires pulled out and then i didnt know the right combo so it was eaier for me to test out of it.

 

[flyhigh123]

The one circuit breaker is on the red wire going to pin 30.

There are no other breakers. Which manual are you looking at? I am looking at the OEM Volvo manual for LK series.

What is your full model number?

I need to find the full model number. Any tips on the location? The manual is ahrd to tell.

I'm looking at this manual:

http://boatinfo.no/lib/volvo/manuals/lk_elect.html#/174

 

[flyhigh123]

If in the process i wired the 12V battery power to lets say the Green/Orange wire, what would it have damaged? The diode? Anything else? Just thinking backwards incase i did something stupid and ran current down a line a shouldnt have.

 

[bruceb58]

Shouldn't have been a problem as long as you didn't have the end of the wire after the diode tied to ground.

 

[flyhigh123]

Bruce: I couldn't find the l2. Here is a picture of the back of the alternator. Is it the pos?

Also in another picture here is the wiring cluster.

This is the following cables:
Purple white
Green
Red/ purple( red turns back onto itself)

Looking at the diagram fun posted should I just connect these directly to the alternator. The other issue is I don't see how these cables are connected to the alternator.

I left my multimeter at home, so i didnt get to check the wiring.

 

[bruceb58]

Are there any unused terminals on the back of the alternator. Anything that has a "D" on it?

There should be an AC tap that goes to your electric choke. Is that wire in that connected mess as well?

 

[flyhigh123]

Are there any unused terminals on the back of the alternator. Anything that has a "D" on it?

When you say "D" you mean on the alternator block body? I'll check tomorrow.

 

[bruceb58]

When you say "D" you mean on the alternator block body? I'll check tomorrow.

Yes.


Look at the last page of this link. The alternator is supposed to be the one in the lower right hand corner. Mando type.
Edit: Iboats blocked the link. Here is the picture after I snipped it.

The D+ terminal is the equivalent to the L2 terminal on the Mando.

 

[flyhigh123]

If the issue was in the starter Diode, then in theory, if i start the engine by putting some gas in the carbs, start it, then in theory, the alternator should be taking over the relay/fuel pump keeping the engine running?

 

[bruceb58]

If the issue was in the starter Diode, then in theory, if i start the engine by putting some gas in the carbs, start it, then in theory, the alternator should be taking over the relay/fuel pump keeping the engine running?

Yes. Once you get that green wire attached to the alternator properly.

 

[flyhigh123]

Also, anyone know what Diode I need? Once i solve the issue, i'd like to be able to replace the diode.

Thanks

 

[bruceb58]

The diodes should still be fine. If you do need to change it out, you don't need a very high current one. One rated for 1A would be sufficient or one bigger just because it will have thicker leads on it.

 

[Fun Times]

Just so you're aware, that alternator doesn't appear to be original. Found your Alt with 2 pretty good photos of the wiring connection points,
http://www.prestolite.com/pgs_produc...uct=Alternator
http://www.bakesonline.com/detail.aspx?ID=1523

Your original Alt may have been Volvo part number 3856600 and would have looked like this ones backside, (Scroll down some)

http://www.ebay.com/itm/MerCruiser-...D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557

For the diode replacement, you may have to try removing it and going to Radio Shack to compare and/or search any info you can find "on" the diode online.

I don't think this Alt offer a second output for say the carb choke or light for additional items. Here's the break down list,

Notes	New, Self Excite Fix circle (Mount): 82.3mm Fix circle (Adjuster): 83.31mm Bracket angle: -30? / 0? / 30? Cut in speed: 1700, Max speed: 8000 Weight: 5.47kg
System voltage	12
Output	105
Mounting style	SPOOL
Dimensions in	INCHES
Rotation	BI-DIRECTIONAL
Housing coating	E-COAT
UL Approved	Yes
Mounting bolt size	.505-.520
Spool length	1
Mounting ear size	5/16-18 NC (3 HOLE)
Mounting holes	3
Positive stud size	1/4-20 NC
Negative stud size	1/4-20 NC
Rectifier location	INTERNAL
Shaft diameter	5/8 INCH
Excitation type	Self Excite
Regulator location	Integral
Regulator number	8RG2043
Diode trio	No
Pulley included	No
Lamp driver	No
Adjustable regulator	Yes
Remote sense	No
Smart check	No
Batteryless	No

 

[bruceb58]

I agree with Fun Times . You need the original Mando style alternator. The one in the lower right corner of the picture I posted is the correct one.

 

[flyhigh123]

I called the alternator company and they said to connect the green wire to the POS terminal. Its for sure not the original and could be why i have that bunch of cables. The alternator works currently so not going to swap it out just yet. But if you feel it affects the function, then i'll def consider it.

thanks!

 

[Fun Times]

I called the alternator company and they said to connect the green wire to the POS terminal. Its for sure not the original and could be why i have that bunch of cables. The alternator works currently so not going to swap it out just yet. But if you feel it affects the function, then i'll def consider it.

thanks!

See where you get and go from there since that is the recommendation from the company....Life would just be easier on you if it was OEM.

 

[bruceb58]

Measure the voltage at that Pos terminal with:

1) Ignition Off
2) Ignition On, engine not running
3) Ignition On, engine running

You should only have voltage with case #3.

EDIT: Just realized this is a self excite alternator which explains the huge clump of wires you have. They wired the ignition(excite) to your green wire because that is the only way to get the pump to run. That is also VERY unsafe. They also wired the choke coil to that excite wire.

The choke coil is supposed to be wired to the AC out of the alternator so that the choke only starts pulling off when the alternator is running. Right now, once you turn on the ignition, the choke will start pulling off.

You need the correct alternator. Sell that one on eBay for someone who wants a one wire alternator.

 

[flyhigh123]

Found both diodes. Its tiny in shrink wrap. I checked the Ohms for each diode. The multimeter would only go in one direction for both diodes. Both diodes read around 470. So I dont know what that means. Was hoping to have 0 on one and a number on the other.

i ordered new relays from Hella as well and thats coming end of week.

When i crank the engine, the fuel pump is reading 12V. The engine will fire once and die. Should I try disconnecting the alternator and firing again and seeing if it reads 12v still?

Is it possible the starter is not sending a single to the starter relay to switch on?