1999 650. Only firing one plug

Are ya having a problem with your rig? We'll try to help. Share your tech tips and experiences here. Dr. Billy Glaser, author of the "Unofficial 750 Ural Service Manual" site myural.com, is moderating this section.
Forum rules
Here is the place for you to ask questions about or share your experiences about servicing or repairing your Ural or Dnepr. Please post topics concering modifications or accesories in the "Modifications and Acessories" section. Please post oil related questions in the "Oil Threads" section.
User avatar
Snakeoil
Order of Suvarov
Order of Suvarov
Posts: 4226
Joined: Sat Nov 29, 2014 9:45 pm
Location: Upstate NY

Re: 1999 650. Only firing one plug

Post by Snakeoil » Thu May 30, 2019 7:11 pm

I noticed that the crank was new. But you mentioned pulling engine and tranny so figured now was the time fo new bearings. Low mileage is not necessarily a good thing. My bad crank did not show up until about 8000 Kms and 17 years.
Regards,
Rob
Proud member of the Peanut Gallery
2000 Ural Tourist
40 Pilots, 122 Mains
Before you say something stupid, always ask yourself, "What would Harpo say?".

URALNUT60
Comrade Colonel
Comrade Colonel
Posts: 388
Joined: Sat Oct 15, 2016 5:59 pm

Re: 1999 650. Only firing one plug

Post by URALNUT60 » Fri May 31, 2019 5:52 am

Snake oil how many miles you have on your new crank? Just put new jap bearings and crank in my 650

User avatar
Snakeoil
Order of Suvarov
Order of Suvarov
Posts: 4226
Joined: Sat Nov 29, 2014 9:45 pm
Location: Upstate NY

Re: 1999 650. Only firing one plug

Post by Snakeoil » Fri May 31, 2019 10:20 pm

I think there are about 14,000 Kms on the rig now.
Regards,
Rob
Proud member of the Peanut Gallery
2000 Ural Tourist
40 Pilots, 122 Mains
Before you say something stupid, always ask yourself, "What would Harpo say?".

Adelphia
Comrade
Comrade
Posts: 32
Joined: Tue May 21, 2019 1:46 am
Location: Philadelphia, PA

Re: 1999 650. Only firing one plug

Post by Adelphia » Sat Jun 01, 2019 11:32 am

Morning!

So we're in it! This is the simplest motorcycle Ive ever been inside of and I honestly wish I'd have known these were like this sooner!

It looks right now like its possible the head gasket blew and was sending exhaust back up the pushrod tube. I see some carbon buildup on that particular head stud and on the gasket itself. I noted what sounded like a hiss going back into the crankcase while turning to TDC.

I also noted today that the inline fuel filters were dry. When I turned the fuel petcock on, they did not fill up. Removed fuel cap and no change. It has a full tank, so that seals the fate of the fuel strainer. Lean condition lead to head gasket/head failure/overheating?

The head wont clear the car to come off completely to better inspect. Must I remove the car, or is their a technique to tilt the engine or even tilt the car a little? I dont have a garage and Id like to be as minimally invasive as possible.
Dustin
2019 Yamaha Bolt R-Spec - 1999 Tourist 650 - 1980 Honda CM200T

Adelphia
Comrade
Comrade
Posts: 32
Joined: Tue May 21, 2019 1:46 am
Location: Philadelphia, PA

Re: 1999 650. Only firing one plug

Post by Adelphia » Sat Jun 01, 2019 11:47 am

No worries. Ill tilt the bike, pull the head, and wrap everything up in preparation to just take the head and have it checked at the machine shop.
Dustin
2019 Yamaha Bolt R-Spec - 1999 Tourist 650 - 1980 Honda CM200T

URALNUT60
Comrade Colonel
Comrade Colonel
Posts: 388
Joined: Sat Oct 15, 2016 5:59 pm

Re: 1999 650. Only firing one plug

Post by URALNUT60 » Sat Jun 01, 2019 2:37 pm

What made the head gasket leak? Million dollar question! I take it piston okay which is good! No scarring on cylinder walls? Do you think head bolts came loose? I wouldn't be afraid to put a torque wrench on the other side, Terry told me with socket head bolts somewhere around 25 ft lbs with copper anti seize on the threads

Adelphia
Comrade
Comrade
Posts: 32
Joined: Tue May 21, 2019 1:46 am
Location: Philadelphia, PA

Re: 1999 650. Only firing one plug

Post by Adelphia » Sat Jun 01, 2019 8:15 pm

The head bolts were tight. I checked them before removing the head, and they definitely had torque on them when I removed the head. It also seemed very even.

Considering the mileage being so low, I have a suspicion that the head may be bad and was bad all along from the factory! The amount or schmutz and hard combustion deposits in the exhaust pushrod tube and on the mating surface of the head tells me so. The machine shop will be able to tell me so, and tell me if its even possible to deck the head back to flat. As for cylinder walls, I did not spin it around to BDC to inspect. They should be just fine and I have faith in that.

When he tells me what it will take to flatten it back out, Ill get with Terry to find out whats the most that can be taken before the deck is too thin and it causes problems and we can go from there.
Dustin
2019 Yamaha Bolt R-Spec - 1999 Tourist 650 - 1980 Honda CM200T

URALNUT60
Comrade Colonel
Comrade Colonel
Posts: 388
Joined: Sat Oct 15, 2016 5:59 pm

Re: 1999 650. Only firing one plug

Post by URALNUT60 » Sat Jun 01, 2019 8:48 pm

Good luck! Hope head is able to be saved!

Adelphia
Comrade
Comrade
Posts: 32
Joined: Tue May 21, 2019 1:46 am
Location: Philadelphia, PA

Re: 1999 650. Only firing one plug

Post by Adelphia » Sat Jun 01, 2019 8:57 pm

Photo of the head. Bottom left is obviously the pushrod tube and the passage for the head stud. Note the black tracking towards those two holes. I neglected to take a photo of the crud in the pushrod tube before cleaning it out, but it definitely had some had burned engine oil in there that broke away when I poked it with my finger. It had created a bit of a ridge around the inside diameter of the tube.

The piston had a bit of a wet look to it, but that may have been engine oil and gas. There also was no slag in the exhaust port from a burned exhaust valve. That doesn't always happen, but it's usually a good sign of it. I think the valve is good.
20190601_141256.jpg
You do not have the required permissions to view the files attached to this post.
Dustin
2019 Yamaha Bolt R-Spec - 1999 Tourist 650 - 1980 Honda CM200T

Adelphia
Comrade
Comrade
Posts: 32
Joined: Tue May 21, 2019 1:46 am
Location: Philadelphia, PA

Re: 1999 650. Only firing one plug

Post by Adelphia » Sun Jun 02, 2019 6:00 pm

I jumped the gun yesterday. A friend asked to see the headgasket itself to give an opinion. While I was at the bike, I decided to turn it to BDC and have a peek at the bore. This turned out to be a great idea. The bore is trashed. There is little to no crosshatching left, there are hotspots burned into it, and an incredibly deep pair of gouges on the rear side. My dial indicator wont fit in there but if they are 5 thousandths deep or more it wouldn't shock me. Even more peculiar is the fact that the snap ring that holds the wristpin in place is in tact. See below.

Severe grooving of the cylinder wall.
20190602_165009.jpg
Wrist pin and snapring intact.
20190602_135514.jpg
Piston and rings showing condition of side of crown and skirt. Click the photo and zoom in. Pay attention to the compression ring and crown on the right side.
20190602_135541.jpg
What caused all of this? What am I looking for here? At this point I am pretty certain I will need to do an entire overhaul of the topend on both sides. If some failure took place I need to correct it now. If this was something overlooked in the previous reassembly I need to make sure it is not repeated.
You do not have the required permissions to view the files attached to this post.
Dustin
2019 Yamaha Bolt R-Spec - 1999 Tourist 650 - 1980 Honda CM200T

URALNUT60
Comrade Colonel
Comrade Colonel
Posts: 388
Joined: Sat Oct 15, 2016 5:59 pm

Re: 1999 650. Only firing one plug

Post by URALNUT60 » Sun Jun 02, 2019 8:37 pm

Ouch! So what do you think caused this?

Adelphia
Comrade
Comrade
Posts: 32
Joined: Tue May 21, 2019 1:46 am
Location: Philadelphia, PA

Re: 1999 650. Only firing one plug

Post by Adelphia » Sun Jun 02, 2019 9:00 pm

No idea. Lack of lubrication? The oil level is normal and is not burned. Heat from lean condition? The missing crosshatch is interesting considering how few kms since the last overhaul, and kms overall.

I was reading that there are "colors" associated with pistons, rings, and cylinders. How does this work? Does this apply here? I see a dot of red paint at the base of the cylinder, and zooming in I see some yellow paint inside of the wrist pin. This means absolutely nothing to me but could to someone here?
Dustin
2019 Yamaha Bolt R-Spec - 1999 Tourist 650 - 1980 Honda CM200T

URALNUT60
Comrade Colonel
Comrade Colonel
Posts: 388
Joined: Sat Oct 15, 2016 5:59 pm

Re: 1999 650. Only firing one plug

Post by URALNUT60 » Mon Jun 03, 2019 5:59 am

When you pulled apart was there a oil film present? Oil in rocker cover when pulled? Bore to piston to tight? Worth a look, early urals had wrist pin issues related to fitment, installed tight, should be able to to install by pushing in with finger, deep scratches concerning, easy enough to pull pump and test! You have investigating to do for sure

User avatar
Mr Wazzock
Hero of the Soviet Union - 2019
Hero of the Soviet Union - 2019
Posts: 5056
Joined: Wed Feb 01, 2017 8:22 pm
Location: Boston, UK
Contact:

Re: 1999 650. Only firing one plug

Post by Mr Wazzock » Mon Jun 03, 2019 7:06 am

Bum. :(
Mike H
2016 Ural cT, in glorious terracotta
(aka Oranzhevaya Opasnost, "The Orange Peril")

URALNUT60
Comrade Colonel
Comrade Colonel
Posts: 388
Joined: Sat Oct 15, 2016 5:59 pm

Re: 1999 650. Only firing one plug

Post by URALNUT60 » Mon Jun 03, 2019 8:36 am

Yellow paint in wrist pin is color matched pin and crank I believe, Terry can confirm for sure

Post Reply