Thursday, March 10, 2016

Ural Engine Assembly - 4

The saga continues. I installed the front bearing on the correct end of the crankshaft and threaded it into the engine case. Following the procedure listed on the myUral website, I picked up the four bolts suggested on the site to line up the rear bearing retainer. They were the wrong size as in wrong thread pitch and wrong length. Back to the hardware store for the correct size. With the front bearing seated in its retainer and the rear bearing retainer seated on the engine case all looks pretty good. But the external snap ring needs the bearing a fraction of a millimeter further for it to seat.

This is the installed rear bearing retainer and it has a thin paper gasket between it and the engine case. The manual said to use a lacquer gasket sealer something I hadn't seen in years. The local Napa store had it on the shelf as aviation engine sealer. A non-hardening sealer that looked exactly like what I've been scraping off of the engine parts. I thought it interesting that there is an odd number of bolts. I still need to remove the bolts and put on some blue thread sealant on them.

The front main bearing in its bearing carrier. It looks like it survived the installation. This is the bearing from Napa. The small tube on the left hand side of the bearing retainer provides oil flow to the timing gear. The lower gear turns clockwise so it carries oil up to the upper timing gear and eventually to the alternator gear.

Jed is stopping by the morning. We'll see how far we get. And with all the running around, the Beemer is getting quite a bit of use.

 

6 comments:

redlegsrides said...

Think of all the experience you're gaining. I hope I can convince you someday to fly in to supervise the inevitable rebuild of my 2014's engine once its out of warranty. ON my dime of course.

RichardM said...

I'm enjoying the experience though I hope I'm doing it right. You need to wait until the engine actually runs (reliably) before making such offers. ;-)

Unknown said...

I haven't dealt with the oil system of new Urals, so I hope you can shred some light on this matter for me. What I'm interested in is how oil is brought to the crankshaft. Does the front bearing holder (or however it's called correctly) have some canals connecting it to the oil pump or something like that?

For example, in Dnipro engines, there is an oil canal from the oil pump to the front bearing holder and from this place into the crankshaft. Here is the article about Dnipro oil system expaining what I mean http://www.cossack-motorcycles.com/2016/01/improving-oil-system-dnipro/

Actually, I would like to know how oil gets to the connecting rods.

RichardM said...

There is a low pressure oil pump with a nozzle that pours oil on the timing gears. This is what lubricates the timing gears, the alternator drive gear, and the front cam bearing. There is a small channel that puts some oil into the upper side of the left cylinder and into the front main bearing. Oil flowing out of the front main bearing gets caught with a slinger mounted to the crank which channels oil into the rod bearing. A similar channel is lubricates the rear main bearing and the other rod bearing. Oil for the rear cam bearing and the lifters is just from oil flying off of the rod bearings. Hope this helps...

Unknown said...

Yeap, this helps, thanks a lot. And what do you think about the efficiency of the system? Is it good enough to keep the engine properly oiled?

RichardM said...

Well, it was abandoned by BMW sometime in the 1950's or thereabouts. I think that it may be adequate under normal use but not when the oil is really viscous such as cold temperatures.