Fluid Treatment and Electrical Work

[qparker4]

Hello,
I'm repairing a 2 stroke 1966 Suzuki b100p and was wondering.. what fluid treatments I should do for an engine and transmission cleanse? Right now I picked up "Sea Foam" gasoline treatment, lead substitute gasoline treatment for an older engine, and Marvel Mystery Oil for the crank case but haven't used any of them. I'm hoping to narrow down the options to one treatment for the gas and one for the oil. Currently there is a lot of build up inside the engine head from what I could see when I took off the exhaust and looked inside. Any help is appreciated.


The electrical question is how can you tell if an old rectifier is blown? Do they need to be grounded? and will replacing a rectifier on a 6v system fix the problem of blowing out headlights or should I just drop it and try to replace it with a newer voltage regulator...which acts as a voltage regulator and rectifier 2 in 1?

[Craig380]

Hi and welcome!

Is the engine still mostly in one piece, with the cylinder head and jug removed, or is it all in pieces? When did it last run? These questions will help to determine the next steps.

I can't really help on the electrical side, I'm afraid, that's a dark art to me

[Vintageman]

The battery is the voltage regulator not the rectifier so you need a fresh battery proper size.

Rectifier turns AC from generator into DC which the battery likes, You can test those rectifiers (diodes) with a voltmeter that has a diode tester function if you think it is bad for example.

Are you not intending to take engine out of bike and/or pop off cylinder?

I would strongly suggest you do. Else grime and grit will ruin engine

Once engine is out clean it as a whole first before you take anything apart. I use gasoline well vented outside away from buildings and a little at a time… into a plastic pan. Kerosene is safer.

I would flush out gear case with gas and a little oil, swish about and drain out until it looks like what you put in. If it has set your clutch maybe be stuck together ... if so have to take off side cover off, clutch cover off and clean and re-oil disk plates.

I would pop of head and jug degrease, decarbonize, wash soap and water and bake at 175F to dry (mmmm wonderful cooking smell again) Or just hot water and wipe. Oil cylinder walls ASAP so no rusting.

I would take off piston too and clean, up to you on this. Look for roughness, gouges etc. Smooth or replace. Check rings and cyl walls for bad looking marks or too much wear. renew, but depends how fuzzy you are. A little wear still run OK. ( how many miles on it)

I would run gas oil mix in crank shaft area and drain a few times until all is clean.

If you don't want to disassemble top end then run gas oil mix and flush out best you can. If drain plug in lower case in crank area that helps. See foam OK, Marvel OK, Polaris makes top end cleaner for 2 stroke snowmobiles forget #) all good maintenance stuff

[pearljam724]

Diesel fuel is a fantastic cleanser for internal motor parts. Makes an excellent flushing fluid.

[qparker4]

Thank you all. The engine has about 16,000 miles on it and I have yet to remove the head and such and the engine is all in one piece so I was hoping to avoid taking the entire thing apart. I will probably remove the cylinder and clean it out best I can, however it does run and seems to shift through all gears decently well. So before I run it further I guess I'll clean out the cylinder and piston with the diesel fuel or a similar solvent.
Also I replaced the battery recently with a new one so I'll have to check out the other stuff because it still blows bulbs when the engine is revved up (at idle it's O.K.)
Thank you again.

[jabcb]

Do you have a wiring diagram?

[Vintageman]

If it runs well you don't want to tear it down but run special sauce in your tank.
Here is one example

http://www.ebay.com/itm/MERCURY-BOAT-PO ... 9e&vxp=mtr" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;

Yes, you could just pop off head an decoke too. You can look at exhaust port and transfer to see how much if any carbon. I'll have to try diesel . Messy stuff . I use it as a mix to oil undercoat my vehicles too!


I don't have wiring diagram (would be nice so no ASSumptions), but believe it is AC generator single coil into four diode bridge rectifier, into battery then all lights run off battery.

So if one of your rectifiers shorted may be passing AC (battery won't clamp opposite polarity). Do you have multi-meter that can test diode (forward and reverse bias?). Even if just Ohmmeter setting you can measure a shorted diode once unhooked (One way my conduct swap leads and then high resistance the other is OK. Conduct a few to Ohms both ways shorted).

Other idea is to measure across battery with meter set to VDC, run engine and see how much if any it climbs above 6-7vdc (is it 6vdc system or 12 VDC?) when you rev it up. If regulated well (not much above 7.x VDC for 6VDC system) try putting meter in VAC mode and see if you get a voltage greater than battery rating. Do this test at head light connection if OK at battery.

Look for missing ground connection from battery to frame... DC side of rectifier should have ground too same as battery... Also make sure both sides of generator coil connected to rectifier diodes (not just one). A connection may be corroded/open.

[jabcb]

Found a wiring diagram:
http://www.andyfox.net/wp-content/uploa ... iagram.jpg

It uses a half-wave rectifier that has a single diode.
The headlight, taillight & speedo light run on AC.
The horn, neutral light & brake light run on DC.

The rectifier doesn't need to be electrically grounded.
But it likely needs to use the frame (or whatever its attached to) as a heat sink.

Am assuming you noticed that the bike will run without a battery.
But the battery is used as the voltage regulator, so you will blow lights if you don't have a good battery.

You can add a voltage regulator to protect the lights from overvoltage.


Your bike uses rectifier 32800-16420 (later part 32800-16421).
http://www.alpha-sports.com/suzuki_parts.htm" onclick="window.open(this.href);return false; (select 1966 & B100)

That rectifier is also used by some of the dirt bikes, like the TS125.
http://www.buymotorcycleparts.com/suzuk ... Inc/TS125_(1971" onclick="window.open(this.href);return false;)/ELECTRICAL/091470001/

[Vintageman]

Found a wiring diagram:

Awesome You took (or put) the ASS right out(in) my ASSumption.

I agree with you. Eventhough headlight AC the positive half cycle is clamped/limitted by rectifier into battery loading.
The negative side is free to increase with RPMs.

This is odd, I have a 1984 SS25 Ski Doo snowmoblile with shunt type Voltage reg. This year one half of it was not clamping and enough to blow head light bulb.

Well check that fuse too.

Are all the lights the right wattage? I would think Suz new what they were doining in 1965?

Another idea is to add a shunt power resistor to AC or power resistor and a diode to suck up some of the extra energy that half cycle.

Or maybe even better run Head light off DC side of battery instaead of AC side.

That head light must be hard to find

[jabcb]

The use of the battery as the only voltage regulator was pretty common back then.

Suzuki continued to use half AC / half DC wiring on their dirt bikes.
The 1971 TS125 is just one example.

You can use a voltage regulator for one of the dirt bikes that has 6V AC/DC wiring + a battery.

[Vintageman]

You can use a voltage regulator for one of the dirt bikes that has 6V AC/DC wiring + a battery.

I looked at 1971 TS125 and did not see a Voltage regulator. Am I missing something or misunderstanding you?

[jabcb]

Was just a generic observation.
Some of the 6V AC/DC dirt bikes have a voltage regulator & some don't.

Am not a dirt biker & haven't chased this down to find an OEM or aftermarket voltage regulator that's suitable for the B100P.

[qparker4]

Great, great stuff. I know my rectifier was not grounded properly (but jabcb you said it didn't need to be...and... just needed to be in contact with the frame to act as a heat sink?))
On the other hand I believe that the battery I purchased is properly grounded. Here's the one I put in http://www.ebay.com/itm/6V-5Ah-SLA-Rech ... 20da352df8" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false; ...

Thanks for the tip about the power tune cleaner as well. The biggest problem when I got the bike was that someone had taken the old battery out and cut all the wires. If I could figure out how to put some type voltage regulator on it I think that would help.
All the lights are the right wattage and voltage too because I have had to buy all new ones due to blowing them out. Also something Vintageman said was interesting (""""I agree with you. Eventhough headlight is AC the positive half cycle is clamped/limitted by rectifier into battery loading...
The negative side is free to increase with RPMs"""")< What do you mean by that?

[Alan H]

On having a better look at the drawing (with my specs on), it appears to be direct lighting fed to the lights straight from the feed side of the charging circuit. The problem could be either a bad dip switch (burnt contacts) or even a wrong type switch, or a wrong wattage headlamp bulb (6v 25/25 watt according to the drawing), or maybe the rear bulb is too small allowing higher voltage to the headlight due to smaller power useage. Check all the bulbs are OK and all the contacts they touch are clean.
Those circuits need a dip switch that has crossover contacts - they are both on for a split second during dip/main operation, unlike 'normal' switches that are either dip or main. This is so the generator voltage can't build during changing from one bulb filament to the other. The lights will get brighter as you rev the engine.

Clever this old tech stuff isn't it?!!?

The rectifier does need to be earthed. The contacts are AC power in and DC + out plus earth to make up the circuit. If your earth is bad or intermittent that can cause problems too. If there isn't a battery or the rectifier isn't earthed, the power from the AC genny will blow the lights as no power will be used by the battery and the feed voltage will go very high. The horn and brake light won't work properly either!

[Vintageman]

they are both on for a split second during dip/main operation, unlike 'normal' switches that are either dip or main.

Alan H I think you are defining "Make before Break" type of toggle switch versus "Break before Make" (that's why if your clever with switch you can make both high and low beams on same time)

Sure that makes sense but does not explain why headlight blows. May explain why tail light would blow out as you switch from high to low beam if broke before made, but not the complaint.

I think I now why all little old on/off dirt bikes have blown head lights.

I agree with jacb the rectifier is just a diode and does not need a ground just heat sinking.

If it were me I would double up on the rectifier and run head light and tail light off battery. May not be as bright that way, but these things weren't much more than few candles. This way you pass inspection.

The reason I would double rectifier for if you pull extra current from DC side more current through rectifier too.


Oh yes, it could just be wrong bulb sizes, missing or open connections, fuse, and make sure that battery has a chassis ground and engine too