View Full Version : timing after rebuild for 185S
hiltu
02-27-2019, 01:58 PM
I thought I timed it right but as im spinning the engine by hand im double thinking myself. With the engine through the see hole at the T mark and the O on the cam sprocket facing straight up with the CDI magnet/rotor corresponding, both the intake and exhaust valves are loose. If I rotate the engine again, it puts the CDI magnet rotor setup up aligning completely down with no free play in the valves. I keep going back and forth on this in my head. I think im right but not convinced. So if I align the T timing mark, the O mark on the cam sprocket with both valves loose (i.e. closed), the CDI magnet rotor with its indicating mark should also be in line with the O mark on the sprocket, not 180* away, or am I backwards? Thanks in advance.
P.S. if you are interested about the engine build:
10.25:1 Wiseco piston
185s cylinder with stock 200S bore
XR185/XR200 cam
new valves/springs and lapped seats
new cam chain and chain tensioners
Also have clutch parts I want to replace (not installed yet)
Gabriel
02-27-2019, 03:29 PM
I've built lots of different engines over the years and I still get that SAME feeling EVERY dang time.
BUT, I figure; Better to be made fun of by the cool kids than crater an engine.
I turn the engine the proper direction and watch the intake valve. SOON as it closes bring the T mark up and stop. If the O on the cam sprocket and the mark on the valve cover line up, you're good. Seat the pulse rotor assembly all the way in, making sure the dowel is in the slot. Set the rotor gap and I like to set the pick up coil by rotating it back and forth to determine dead center. You can adjust with a light later. Set the valve lash. Get it started.
There's no shame in quadruple checking everything before you start it. I will gauran-damn-tee you any race engine builder worth his salt builds an engine like Santa Claus.......Makin' a list...checkin' it twice.
Reading the manual, taking notes and making a check list to mark off as you go is NOT a dumb idea.
Something else I do, leave the plug out and crank the engine several times first. Easy and feel for something that ain't right...then faster and faster. This is exponentially easier on an electric start. Helps prime the oil pump and get some oil in the places it needs to be.
I was so paranoid on this last 200ES motor I did ( I had a LOT of time and money in it...not just a fresh top end) I actually poured about 1/2 a cup of fresh oil in through the valve cover plug so there'd be oil up there the instant it fired. That's on top of copious amounts of assembly lube.
Good luck! Hope that helps...it probably didn't. LOL!!!
350for350
02-27-2019, 08:47 PM
Gabriel, if I remember right, doesn't the manual usually say to fill the spot under the cam lobes with oil before starting it?
hiltu
02-28-2019, 09:02 PM
350for350, at least 1 of the 2 manuals im using states to do that.
350for350
02-28-2019, 09:29 PM
I guess Gabriel thinks like Honda does.:cool:
Scootertrash
03-02-2019, 08:14 AM
Something else I do, leave the plug out and crank the engine several times first. Easy and feel for something that ain't right...then faster and faster. This is exponentially easier on an electric start. Helps prime the oil pump and get some oil in the places it needs to be.
I was so paranoid on this last 200ES motor I did ( I had a LOT of time and money in it...not just a fresh top end) I actually poured about 1/2 a cup of fresh oil in through the valve cover plug so there'd be oil up there the instant it fired. That's on top of copious amounts of assembly lube.
I do the same with every engine I build, but I use a power drill to turn over the engine. I use an old 1950's 1/2 inch drill, low RPMs but plenty of torque. I put a paddle mixer in the same drill for mixing tile thinset and grout. This thing will stir set concrete. The other nice thing is it's rebuildable, brushes and bearings are still available.
Gabriel
03-02-2019, 08:55 AM
I seem to recall reading once about packing the oil pump with Vaseline to make it prime faster
Not sure I wanna try that but curious if anyone else has.
Scootertrash
03-02-2019, 09:02 AM
Gabriel, does glamy know you're up dis early??:naughty::lol:
I've heard of the vaseline trick, but the only place I've used it is in a couple of Chevy 350 engines. The motors were still running when I sold them years later.
Powered by vBulletin® Version 4.2.2 Copyright © 2024 vBulletin Solutions, Inc. All rights reserved.