Sluggish starter issue - with full charged battery

[Mucci]

Hi guys,
New to the forum, but just got an 83 R65 in the garage so I imagine I'll be on here quite a bit now.

The bike will not start. With the battery on full charge, the bike will very sluggishly try to turn over, then just click-click-click.

We even tried running leads to the bike from a car battery with the car running and the starter is still very sluggish and won't turn over. It's as if something is preventing all the power to get to the starter.

Any ideas why this could be?

Thanks Dave

[Barry]

Welcome Dave

Assuming all connections are clean and tight it could be a faulty starter. Is it a Bosch  or Valeo ?

On early Valeo starters the magnets could come adrift and jam the starter.

First  thing to establish is whether it's a starter or cabling/solenoid fault i.e is the starter is trying to draw the correct current or not.

You can check that by measuring the voltage at the battery terminals while operating the starter. You should expect to see the voltage drop to approx. 10.5 volts if the starter is drawing something like the correct current. If it is then you have a jammed or seized starter. If not then there is something wrong in the cable connections or starter soleniod.

[Bob_Roller]

When you use the car to try to start the bike, is the bikes battery still connected ?

You may have a faulty battery .

If you can, try using the jump start method with the bikes battery disconnected .

[Mucci]

When we used the cars battery the connections were directly to the bikes cables. No battery in the bike.

Why disconnect the battery when run starting it?

I'll go through the above checks. Thanks guys

[montmil]

When we used the cars battery the connections were directly to the bikes cables. No battery in the bike.

Why disconnect the battery when run starting it?

I'll go through the above checks. Thanks guys

Bob means to take the battery out of the system when attempting to "jump start" the bike from another battery source. Not the old GP run n' bump method.

Confirm all wires in the starting system are clean and snug. You'll need to remove the engine top cover to complete this check. How old is the battery? With the old battery still in the power loop and a second battery connected, you may not have much luck... as you've already discovered.

Could be old, hardened grease in the starter. Removal is simple as is a cleaning, rebuild or replacement.

But first go through the wiring checks. Consider a possible wire partially broken under the vinyl covering. Forego buying possible unneeded parts until you determine exactly what is wrong.

Check back later and share what you find. It will be something simple. Really.

Monte

[tvrla]

First off, it's not a good idea jumping a bike from a running car. A car battery is way plenty strong enough all by itself without having the engine running. I've heard it's possible to damage the alternator if the car is running, but don't know if that's true or not, as I've done it myself before with no ill effect. Still, having the car running isn't necessary.

The reason you've been told to remove the battery from the circuit is because it's possible for one of the cells in your battery to be shorted to ground. When the car battery is hooked to your cables (that are still attached to your battery terminals) the car's electricity will just short out back to the car and never reach your starter.

Only one of your battery leads needs to be removed to test that. The way I'd do it is jump to your battery terminals. No start? Remove the negative lead and bypass your battery. No start?

Next step: Perhaps there's a bad connection or bad lead to the starter.

Test that possibility by bypassing the leads to the starter totally. Connect the positive jumper to the bolt-on connection where the main large battery lead connects. Clip the negative lead to the starter body or a mounting bolt. The starter grounds through its mounting.

Then, to activate the starter, the solenoid needs to be energized. There's a spade terminal to the solenoid that comes from the starter relay. I believe it's black (recall could be off) but what needs to happen is 12V needs to arrive at that connection. So either jumper 12V to that connection or simply touch the tip of a screwdriver to the hot jumper cable and drape it over that spade terminal.

The starter should leap to life, and hopefully the bike is on the center stand in neutral.  

If the starter still doesn't work, you'll know there's something wrong with the starter. I suspect you've got a Bosch, and what happens with them is the bushings wear and you get symptoms as you're seeing now.

Let us know what you discover.

[k_enn]

First check the other stuff like the guys said, but it could well be the starter.  The one on my 1982 gave it up earlier this year.  All kinds of little copper bits came tumbling out of it when I removed.  

If the starter is dead, its your choice whether to rebuild or replace.  I chose to replace, and found the Valeo far easier on the wallet than a Bosch.  
Here is a link -- these guys were prompt:

http://www.euromotoelectrics.com/Starter_BMW_R_Airhead_9_Tooth_BMW_VAL1_p/bmw-val1.htm

k_enn

[Mucci]

Ok, so as we dive deeper, we're finding more and more issues.

We found that the battery was dead. He has since bought a new battery. We also cleaned up all the connections and grounds we could find.

The bike now turns over healthily as it should - however, still does not fire up.

We have replaced the plugs and have taken each out and verified that spark IS getting to the plugs.

The engine is turning and the spark is firing... so must be fuel I assumed. We tried starting it while blasting carb cleaner into the air box, and not one blip.

We removed the carb bowls to find this:





Rusty latte mixture. We also looked in the tank and found what appeared to be tomato bisque, but I'm assuming didn't taste as delicious.

Since that discovery, we cleaned and rebuilt the carbs:

We dissembled everything, and soaked the bodies in carb cleaner for about 2 hours.



The brass bits went in CLR



The bodies and non brass bits went into the ultrasonic cleaner, using Simple Green Pro HD, for about 30min





With everything all cleaned up, we rebuilt the carbs. All gaskets and o-rings were replaced, new float needles, diaphragms, etc.





We put the carbs back on the bike. Replaced the fuel lines, and fuel filter, and used a tank off a different bike as a fuel basin, since the BMW tank hasn't been cleaned out yet.

The bike still will not start...  Again it turns over in a healthy manner, and spark is getting to the plugs, but not a blip of hope from the exhausts.

At that point it had already been a 10hr day so we left it. Any ideas on where to go from here? Could that rusty mixture having got into the cylinders built up an internal issue preventing combustion? I'm out of ideas for now.

[Bob_Roller]

When you cleaned the carbs, did you make sure that all of the passageways in the carb body are cleaned out ?

Have you checked the plugs after several start attempts ?

Are the plugs wet, or dry ?

What color is the spark at the plugs ?

If you still have the OEM grey and black ignition coil, it's a known weak point in the ignition system .

[Mucci]

Yes, after taking the carbs out of the carb dip, we blasted out all the passages with carb cleaner. Then put them in the ultrasonic cleaner. Then blasted the passages out with compressed air.

We haven't checked the plugs since the cleaned carbs went back on. I will check next time and check for fuel on the tips.

The new plugs haven't seen any attempt at combustion, so I would think there shouldn't be any discoloring.

The coils are all black if I recall correctly. Where can I find the PN for the original problematic coils?

[Bob_Roller]

Sounds like you have a previous owner 'modification', if you have more than one coil .

The OEM coil is a single coil with dual outputs .

[Barry]

Carbs look great !


Has Ignition timing been checked

Have you done a compression test or at least a check that valve clearances haven't closed up.

[tvrla]

Are you positive the chokes went back together correctly? Are the choke jets in the float bowl free and clear?

Normally, a bike will start on ether even if the spark is weak. So it's not a good sign it wouldn't even try. I'm wondering if something isn't wrong with the ignition. One of the weirdest I've had to figure out was a bad bean can (hall sensor). It would spark sometimes which lead me to think everything (ignition wise) was ok, when in fact, the plastic hall sensor had broken loose from its mounting and would now and then work. But the timing was all off, so even when there was spark, it didn't come close to sounding like it would start.

As a first test, find out if you're getting spark at the proper time.

[montmil]

For now, let's assume the chokes are reinstalled and operating correctly.

With the chokes engaged -these are actually more like small carburetors within the larger carb, hence the correct term being "enrichener circuit"- starting fuel will be drawn from a small vertical reservoir fed by a tiny 'jet' at the bottom of the well. With the carbs assembled, there is a brass tube in the reservoir that feeds the enrichener circuit. If that little 'vent port is clogged up and closed off, it will be exceedingly difficult to get fuel into the cylinder and smoke out the tail pipe.

From the looks of your float bowls, I'd drop 'em off and double check to see if you have fuel flow into the enrichener reservoir. Thin piece of copper wire will open the port without damaging anything.

When my old lawn mower was reluctant to light off, I'd pull the spark plug and add a few drops of petrol. Next rope pull... va voom! Go ghetto and try it on the Beemer. If it fires, you may not be getting fuel into the cylinders.

[Mucci]

We'll perform a few of these checks this weekend hopefully and I'll report back.

Also, one hang up we had was with the new float needles. The old float needles had a very thin gauge wire attached to the end, in a paperclip style orientation.

The new float needles (genuine BMW) did not come with this piece, and the repair manual says nothing about it. I've got a CX500, and I know on those carbs a piece similar to that was used to attach the float needle to the floats. Is this how that part should be treated on these carbs as well?

I assumed it was, so that's what we did, however with the range of movement the floats have, it doesn't appear the needles would be allowed to remove themselves anyhow.

Thanks for the help guys.