Author Topic: Phoenix Rising - '93 K75RT Fire Recovery  (Read 4666 times)

Offline brichbk

  • ^ Motobrick Curious
  • Posts: 102
Re: Phoenix Rising - '93 K75RT Fire Recovery
« Reply #50 on: October 29, 2018, 01:31:18 PM »
I got all the valves adjusted with new shims using the Ken Lively tool (which worked great).  The intake valves are all at a .20 mm clearance and the exhaust are all at .25 mm for clearance.

I can confidently say that it seems like the bike is back to the pre-fire state.  That is the good news.  Now the bad news.

I went to balance the throttle bodies with my new Motion Pro manometer only to have the #3 cylinder do nothing.  #1 & #2 both adjust and the fluid goes up and down when the throttle is turned.  I tried switching the vacuum lines around on the manometer and throttle bodies and no changes, which ever hose is on #3 doesn't register.  So I switched the #1 and #3 injectors and no changes, #3 still doesn't register on the manometer.  I confirmed spark on all spark plugs and even switched #1 & #3, still no change.  It appears that my #3 cylinder is not functioning (no compression?).

I borrowed my friend's compression gauge and plan on checking compression on all my cylinders tonight.   Is there another thing I should check?


For reference here is my original post on the same issue, http://www.motobrick.com/index.php/topic,11083.msg96575.html#msg96575.
  • Central Valley California
  • 1993 BMW K75RT // 1982 Honda Nighthawk 650sc

Offline Laitch

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  • Posts: 5936
Re: Phoenix Rising - '93 K75RT Fire Recovery
« Reply #51 on: October 29, 2018, 04:15:44 PM »
Which balance procedure instructions are you using?
  • Along the Ridley in Vermont.
  • 1995 K75T 68,000 miles
I wept because I had no radials until I met a man who had no splines.
http://www.motobrick.com/index.php/topic,296.msg53303.html#msg53303

Offline brichbk

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  • Posts: 102
Re: Phoenix Rising - '93 K75RT Fire Recovery
« Reply #52 on: October 29, 2018, 04:41:34 PM »
I was following the instructions in my chlymers manual and from the Motion Pro instructions.
  • Central Valley California
  • 1993 BMW K75RT // 1982 Honda Nighthawk 650sc

Offline Martin

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Re: Phoenix Rising - '93 K75RT Fire Recovery
« Reply #53 on: October 29, 2018, 05:27:55 PM »
Remove the adjusting screw and check for blockages.
Regards Martin.
  • North Lakes Queensland Australia
  • 1992 K75s Hybrid, Lefaux, Vespa V twin.

Offline brichbk

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  • Posts: 102
Re: Phoenix Rising - '93 K75RT Fire Recovery
« Reply #54 on: October 29, 2018, 06:20:09 PM »
Remove the adjusting screw and check for blockages.
Regards Martin.

Thanks Martin, am I correct in assuming the adjustment screw is the brass screw?  I’ll check that out while I wait for my battery to charge up. 
  • Central Valley California
  • 1993 BMW K75RT // 1982 Honda Nighthawk 650sc

Offline Laitch

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Re: Phoenix Rising - '93 K75RT Fire Recovery
« Reply #55 on: October 29, 2018, 07:39:13 PM »
am I correct in assuming the adjustment screw is the brass screw? 
You shouldn't be assuming anything while doing this procedure or any other. Fig. 61 on page 245 in my Clymer's show the air bypass screws to adjust. Fig. 60 shows the screws not to adjust. The two different screw types look distinctly different.
 :yippee:


 :grimreaper:
  • Along the Ridley in Vermont.
  • 1995 K75T 68,000 miles
I wept because I had no radials until I met a man who had no splines.
http://www.motobrick.com/index.php/topic,296.msg53303.html#msg53303

Offline The Mighty Gryphon

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Re: Phoenix Rising - '93 K75RT Fire Recovery
« Reply #56 on: October 29, 2018, 07:52:18 PM »
+1 on Martin's suggestion to remove the brass balancing screw.  You probably have some crap in the orifice.  Shoot some carb cleaner into the orifice that the screw goes into and try balancing again.. 
  • In my garage in Marilla, NY
  • '94 K75RT Mystic Red, '92K100RS White, '94 K75S Dakar Yellow
Current:
'94 K75RT "Ilsa, She Wolf of the SS"
'94 K75S "Cheetos"
'91 K100RS "Moby Brick Too

Offline brichbk

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  • Posts: 102
Re: Phoenix Rising - '93 K75RT Fire Recovery
« Reply #57 on: October 30, 2018, 01:21:33 AM »
So removed each adjustment screw one by one and cleaned out each orifice.  The #3 was definitely dirtier than #1 & #2.  Reran the test and it didn't seem to make a difference.  #3 still isn't showing up on the manometer.  Could it be a clogged vacuum pipe/nipple on #3 (the hose that connects to the fuel pressure regulator)?  Should I pull the throttle bodies to be able to give the adjustment screw orifices and the vacuum connections a better cleaning?

I ran out of time to do the compression test on the cylinders, so that still needs to be done.

I read a post that referenced pulling the plug wire while the bike is running to check to see if the cylinder is firing or not.  Is this something I should try or is it bad for the ignition system?
  • Central Valley California
  • 1993 BMW K75RT // 1982 Honda Nighthawk 650sc

Offline The Mighty Gryphon

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Re: Phoenix Rising - '93 K75RT Fire Recovery
« Reply #58 on: October 30, 2018, 09:13:51 AM »
Could it be a clogged vacuum pipe/nipple on #3 (the hose that connects to the fuel pressure regulator)? 

I strongly suggest you clean out that nipple.  Lots of carb cleaner and compressed air.  Stick the red tube in there as far as you can. 

Was the bike running before the fire?  If so, I would say the compression is good.  If you suspect a stuck ring, then I would suggest putting a pint of Marvel Mystery Oil in the crankcase.  I had a K100RS with a stuck oil control ring that was making the bike burn a lot of oil.  The Marvel Mystery Oil freed it up in less than a thousand miles.
  • In my garage in Marilla, NY
  • '94 K75RT Mystic Red, '92K100RS White, '94 K75S Dakar Yellow
Current:
'94 K75RT "Ilsa, She Wolf of the SS"
'94 K75S "Cheetos"
'91 K100RS "Moby Brick Too

Offline Laitch

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Re: Phoenix Rising - '93 K75RT Fire Recovery
« Reply #59 on: October 30, 2018, 10:39:09 AM »
Was the bike running before the fire? 
The coils were replaced in May. The moto seemed to be idling ok. brichbk stated it ran like a bat out of hell but it still wasn't satisfactory so he did the injector spray test and that's when the fire started. Cylinder #3 has shown problems since the beginning of this epic. It is also the cylinder that had the tightest clearance according to brichbk's measurements.

The attached image shows what appears to be a missing vacuum cap at cylinder #3 and much debris #3's injector opening so clog possibilities exist. Because that cylinder seems to have a history of malfunction, I would do a compression test, or leakdown test asap.


  • Along the Ridley in Vermont.
  • 1995 K75T 68,000 miles
I wept because I had no radials until I met a man who had no splines.
http://www.motobrick.com/index.php/topic,296.msg53303.html#msg53303

Offline brichbk

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  • Posts: 102
Re: Phoenix Rising - '93 K75RT Fire Recovery
« Reply #60 on: October 30, 2018, 11:34:12 AM »
The coils were replaced in May. The moto seemed to be idling ok. brichbk stated it ran like a bat out of hell but it still wasn't satisfactory so he did the injector spray test and that's when the fire started. Cylinder #3 has shown problems since the beginning of this epic. It is also the cylinder that had the tightest clearance according to brichbk's measurements.

The attached image shows what appears to be a missing vacuum cap at cylinder #3 and much debris #3's injector opening so clog possibilities exist. Because that cylinder seems to have a history of malfunction, I would do a compression test, or leakdown test asap.

Laitch, what you say is correct.  The picture you posted was after the fire so the "missing vacuum cap" is actually the melted vacuum hose.  But #3 was definitely the dirtiest after the fire to clean up.  I'll do a compression test later today and I'll work on cleaning of the vacuum nipple.
  • Central Valley California
  • 1993 BMW K75RT // 1982 Honda Nighthawk 650sc

Offline brichbk

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  • Posts: 102
Re: Phoenix Rising - '93 K75RT Fire Recovery
« Reply #61 on: October 30, 2018, 04:24:49 PM »
Just finished the compression check and here are the results:
Cylinder 1 — 145
Cylinder 2 — 150
Cylinder 3 — 0 (less than 10)
Added 8cc of oil and remeasured #3 — 0 (less than 10)

Test was done on a fully charged battery, wide open throttle, warmed up engine, and screw in compression gauge.
  • Central Valley California
  • 1993 BMW K75RT // 1982 Honda Nighthawk 650sc

Offline Laitch

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Re: Phoenix Rising - '93 K75RT Fire Recovery
« Reply #62 on: October 30, 2018, 05:33:05 PM »
Just finished the compression check and here are the results:
Cylinder 1 — 145
Cylinder 2 — 150
Cylinder 3 — 0 (less than 10)
Cylinders #1 and #2 are on the cusp of the high-normal and low-good ranges according to BMW's 2V manual. Continued operation of this engine could have broken the #3 exhaust valve or dropped its valve seat then ruined the engine entirely so there's still some good luck surrounding this situation. Depending upon the condition of the head when it has been removed and inspected, the head might be repairable. Used heads are available, of course.
  • Along the Ridley in Vermont.
  • 1995 K75T 68,000 miles
I wept because I had no radials until I met a man who had no splines.
http://www.motobrick.com/index.php/topic,296.msg53303.html#msg53303

Offline brichbk

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  • Posts: 102
Re: Phoenix Rising - '93 K75RT Fire Recovery
« Reply #63 on: October 30, 2018, 07:13:17 PM »
Cylinders #1 and #2 are on the cusp of the high-normal and low-good ranges according to BMW's 2V manual. Continued operation of this engine could have broken the #3 exhaust valve or dropped its valve seat then ruined the engine entirely so there's still some good luck surrounding this situation. Depending upon the condition of the head when it has been removed and inspected, the head might be repairable. Used heads are available, of course.

So, what I'm hearing from you is that it's possibly not at a catastrophic stage and is possibly repairable, is that correct?  Next steps would be, remove and inspect the head, and valves? That would definitely be new territory for me.
  • Central Valley California
  • 1993 BMW K75RT // 1982 Honda Nighthawk 650sc

Offline Laitch

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Re: Phoenix Rising - '93 K75RT Fire Recovery
« Reply #64 on: October 30, 2018, 07:47:36 PM »
So, what I'm hearing from you is that it's possibly not at a catastrophic stage and is possibly repairable, is that correct? 
How could I have made my statement more clear?
  • Along the Ridley in Vermont.
  • 1995 K75T 68,000 miles
I wept because I had no radials until I met a man who had no splines.
http://www.motobrick.com/index.php/topic,296.msg53303.html#msg53303

Offline brichbk

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  • Posts: 102
Re: Phoenix Rising - '93 K75RT Fire Recovery
« Reply #65 on: October 30, 2018, 08:12:18 PM »
How could I have made my statement more clear?

Sorry Laitch, I'll try not to irritate you with worthless questions. 

I'm reading through this site http://www.bmw-k100rt-page.eu/manual/Engine/contentEngine.htm to get an idea of what is all required to check out the heads.



  • Central Valley California
  • 1993 BMW K75RT // 1982 Honda Nighthawk 650sc

Offline Laitch

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Re: Phoenix Rising - '93 K75RT Fire Recovery
« Reply #66 on: October 30, 2018, 08:38:52 PM »
Sorry Laitch, I'll try not to irritate you with worthless questions. 

I'm reading through this site http://www.bmw-k100rt-page.eu/manual/Engine/contentEngine.htm to get an idea of what is all required to check out the heads.
You're probably looking for confirmation about all this. Maybe somebody else here will chime in, one way or the other.

Inspecting the cylinder head will take somebody with general automotive or motorcycle repair and machining experience. Start looking for somebody that can inspect it. A BMW specialist won't be necessary at this point.
  • Along the Ridley in Vermont.
  • 1995 K75T 68,000 miles
I wept because I had no radials until I met a man who had no splines.
http://www.motobrick.com/index.php/topic,296.msg53303.html#msg53303

Offline The Mighty Gryphon

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Re: Phoenix Rising - '93 K75RT Fire Recovery
« Reply #67 on: October 30, 2018, 09:20:49 PM »
If you decide to remove the head, try to get a pneumatic impact wrench.  You will also need a special heavy duty torx wrench to break the head bolts loose.  I tried to do mine with a breaker bar.  What an appropriately named tool!  I broke one of the bolts off just below the surface of the block.

The special Torx wrench is a different size and shape from the regular ones.  If you don't use it, you will probably bugger up the head of the bolts. 

https://www.ebay.com/itm/TEMO-IP-50-3-Long-Black-Impact-Torx-Plus-6-point-Socket-Bit-1-2-Square-Drive/132204305289?epid=1339458897&hash=item1ec7fd9b89:g:K~MAAOSwrVRbWd5E:sc:USPSFirstClass!14052!US!-1:rk:11:pf:0

The head bolts are under a lot of torque, and there is a chance of corrosion on the threads.  An impact wrench is the gentlest way to break them loose.  Wish I had used it when I did mine.  Would have saved me an extra two weeks of work trying to remove and helicoil a broken off hardened bolt.
  • In my garage in Marilla, NY
  • '94 K75RT Mystic Red, '92K100RS White, '94 K75S Dakar Yellow
Current:
'94 K75RT "Ilsa, She Wolf of the SS"
'94 K75S "Cheetos"
'91 K100RS "Moby Brick Too
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Offline caveman

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  • Posts: 67
Re: Phoenix Rising - '93 K75RT Fire Recovery
« Reply #68 on: October 31, 2018, 04:40:12 AM »
With the correct torx-PLUS bit and a hammer impact a few sharp blows should free bolts with less chance of damage. If you do use air impact turn down the pressure (start with 30 to 40 psi), most gun run wide open in reverse and can snap off bolts faster than a breaker bar.
  • Kennerdell, PA.
  • 87 K100RT, 88 K100LT

Offline brichbk

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  • Posts: 102
Re: Phoenix Rising - '93 K75RT Fire Recovery
« Reply #69 on: October 31, 2018, 09:34:16 AM »
Thanks Caveman and Gryph for the advice.  Anyone have any more advice before I start in on this project?
  • Central Valley California
  • 1993 BMW K75RT // 1982 Honda Nighthawk 650sc

Offline Laitch

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  • Posts: 5936
Re: Phoenix Rising - '93 K75RT Fire Recovery
« Reply #70 on: October 31, 2018, 11:08:43 AM »
Do your research concerning the shop that will analyze the condition of the cylinder head.
Read instructions for disassembly and assembly from beginning to end a couple of times before starting this project. Review instructions from two or more sources if possible and reconcile any differences in them before starting this project.
Don't assume anything.
Exercise patience.
Wear knee pads.
Have a headlamp available.
Have a telescopic magnet available.
Wear mechanic gloves when wrenching although scarred hands increase street cred while riding the bus.
Thoroughly clean all surfaces involved in disassembly.
Photograph assemblies before and during disassembly.
Organize and label disassembled parts.
Label wiring.
Be certain to verify when to use a standard Torx bit or Torx Plus bit.
Use a heat gun to heat stubborn fasteners first then use penetrant on them. Knock them with a hammer a couple of times, wait a few minutes then attempt to loosen them. Repeat.
Don't assume anything.
Exercise patience.
Take a break from frustration.
Clean all surfaces thoroughly before reassembly.
Use a high quality torque wrench for reassembly and follow tightening sequences explicitly.
Exercise patience.
Take a break from frustration.
  • Along the Ridley in Vermont.
  • 1995 K75T 68,000 miles
I wept because I had no radials until I met a man who had no splines.
http://www.motobrick.com/index.php/topic,296.msg53303.html#msg53303
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Offline The Mighty Gryphon

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Re: Phoenix Rising - '93 K75RT Fire Recovery
« Reply #71 on: October 31, 2018, 01:37:44 PM »
I pulled the head off of my K100 in the winter.  Parking the bike on a 6'x8' chunk of plush carpet made working on the floor infinitely more pleasant.  It cushions under your knees and insulates you from the cold floor.  I do all my work with the bike parked on the rug.

Buy a box of zip lock sandwich bags and a Sharpie marker.  As you take things apart put fasteners and small parts in the bags and label the bag for where they came from.
  • In my garage in Marilla, NY
  • '94 K75RT Mystic Red, '92K100RS White, '94 K75S Dakar Yellow
Current:
'94 K75RT "Ilsa, She Wolf of the SS"
'94 K75S "Cheetos"
'91 K100RS "Moby Brick Too
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Offline Martin

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Re: Phoenix Rising - '93 K75RT Fire Recovery
« Reply #72 on: October 31, 2018, 04:08:50 PM »
+1 on Sharpies and Zip Lok bags. Take pictures with your phone or camera. I bought a piece of 30mm thick closed cell foam to kneel or lie on.

Regards Martin.
  • North Lakes Queensland Australia
  • 1992 K75s Hybrid, Lefaux, Vespa V twin.
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Offline riots100

  • ^ Proficient Motobricker
  • Posts: 142
Re: Phoenix Rising - '93 K75RT Fire Recovery
« Reply #73 on: October 31, 2018, 05:37:48 PM »
Pulling the cylinder head isn't that hard to do, as mentioned by others, the issue is to keep all the parts and pieces together.  Zip lock bags and the camera-phone helps to get things back together in proper order.

To pull the head, you will have to pull the timing chain sprockets on the camshafts.  It is important that you note which cam the timing chain sprocket came from as they will have to go back on the same camshafts.

So careful documentation of disassembly will greatly help in re-assembly.

A while ago I had to do a partial engine rebuild that included cylinder head removal and reconditioning.  It is documented here:
http://www.motobrick.com/index.php/topic,7661.0.html
  • Los Angeles, CA
  • 1992 K75, 2007 K1200GT, 1991 K100RS
----
BDJ
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Offline brichbk

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  • Posts: 102
Re: Phoenix Rising - '93 K75RT Fire Recovery
« Reply #74 on: November 10, 2018, 01:35:09 AM »
I started the engine disassembly today (pics below).  Got all three engine covers removed (crankcase, camshaft, and valve), removed the radiator, exhaust and muffler as a single unit.  I suspect that it will take twice as long to put everything back together simply because every screw and piece needs a good thorough cleaning.  Tomorrow I'll start to separate the blocks.

Valve side with cover removed.  I looked up into the valve exhaust ports to see if I could see the valves, but I couldn't really see anything of detail.


Crankcase side with cover removed.  Took a peek at the connecting rods and they look straight and not bent. 


Camshaft (front) with cover removed.  Notice the dirty water pump fans blades (?)


Inside of exhaust headers.  Notice the carbon build up in each except #3


  • Central Valley California
  • 1993 BMW K75RT // 1982 Honda Nighthawk 650sc

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