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GSjimmy

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Discussion starter · #1 ·
For those who have been following the build thread, I am in need of ideas on getting the bike sorted.

I've been trying everything to get going with this bike. Even my mechanic look at it. Compression is fine, timing was reset (off a tooth) to the "T" mark. Reran the valve lash and timing chain tensioner. Then I was able to get it to take throttle once over the weekend (sounds great). It idles great, but falls on its face when throttle is applied, other than with the fuel off and carb about empty, then it took throttle.

Then my issue must be in the carb. Leads me to think it is either float related or fuel staving at the petcock/fuel line. I'm going to order a KDX80 petcock that has a reserve feature and a side discharge to straighten out the fuel line. Right now I have a funky bend in the line that I'll try to straighten out tonight. I also need to check on the float as I still get some gas dribble at the overflow (float up some?).

My only other long shot is that the needle is in the wrong position.

IDEAS????
 
Discussion starter · #2 ·
Well, I know what it isn't. I checked on the needle position & carb last night. Clip is in the 2nd from the bottom. Moved it to the 2nd from the top, no run. Center, no run. Back where it was, runs fine (at idle). So when the throttle is cracked open, it sounds like it runs out of fuel, wierd. So I took a real good look at the fuel line. It has a small "dip" that seems to hold an air bubble. Since the petcock has a broken lever, I ordered a KDX80 replacement petcock, same part, but side discharge & reserve feature. This will allow the fuel line to reroute and should eliminate the bubble in the line (I hope). Part needed to be changed out anyway.

I also fouled out a plug. Fresh plug and it poped off & idled fine. So I guess if the the bike still runs rich, the 33 year old carb might be a problem. I am getting closer though.
 
Discussion starter · #3 ·
What it isn't

Just installed the keyway last night. Fired it up...........same problem.

So since everything has been verified “good” I’m down to a possible air leak at the manifold?????

Got some liquid plastic and will go over the rubber section were the aluminum meets the rubber isolator, focusing on the connections inside & out. It this cures it, I need to talk with a buddy who has a lathe and turn one out of aluminum stock (3” x 8” bar stock). That would insure that there is no leaks as it would be solid aluminum.

Thoughts on that one?

Jim
 
Discussion starter · #5 · (Edited)
Yeah, been over them 100 times and all are bare steel connections. I did finally break down and buy the manual last night. I also pulled the enginge and tore it back down to verify that everything is installed correctly. The piece of info I don't have is if the engine times at BTDC or at TDC. I have it at TDC, arrow on the pistion facing forward (WISECO). Timing mark at "T" and dot straight up on the cam gear.

So if this times at BTDC, then I'm (stupid) 180* out and that explains the timing issue. This could be it I guess. At this point I am more than a bit frustrated with this engine.

Verified good parts: Intake, carb, flywheel, stator, coil, plug, condensor, points, keyway, electrical connections. Runs at idle, verified correct rotation of the engine.
 
Discussion starter · #6 ·
I now know what is wrong (the hard way)

Well, I got it figured out.

The timing chain & gears.

Saturday I got it to take throttle and was running it to break in the piston/rings when it came to a sudden stop. Not good. So I verified that it won't turn over and pulled the engine again. Took off the valve cover and found....

A broken cam gear, backed out bolt and missing timing chain. Kinda explains what's going on. So I tore down everything to find a small piece of metal from the timing gear failure. Interesting what all ends up in the crankcase. I found the metal bits before any real damage happened. The failed bolt was easy to get, but the gear was broken in half. Timing chain is streched so it goes into the recycle bin.

So since everything is apart, I will do a through cleaning and detail of the engine, looking for any/all bad parts and will paint it semi-gloss black, sand off the fins on the edge and leave the polished valve cover alone. I just ordered gaskets, t. chain, oil seals, valve seals, cam gear (HONDA) and bolts. I did need to drill out 2 pan head screws to get it apart, so those are on the list also.

Everything should be in next week, and I'll do all the clean up this week. Still need to paint one side of the case, and the clutch cover. When done this will be a fully rebuilt engine as my oldest will be doing the head this week. I am also able to "cure" the valve stem leak at the same time (bonus). Sux to find out things the hard way.

Jim

I also get to rebuild a Nissan 3.3 short block (O' fun) in a Pathfinder, oldest oil starved it a spun a main (load deep knock). Hoping he didn't wipe out the crank too (45,000 mile engine).
 
Discussion starter · #7 ·
Cases have been completly disassembled and cleaned. Painted everything semi-gloss black and baked at 170* for 20 minutes. This should help cure out the paint and "harden" it enough to resist some of the scratches. Not going for perfect, as the boy will be riding this one in the woods and on a track.

Parts started to show up yesterday, installed the oil seals last night and got everything sorted out. The gaskets show up later this morning and the manual on Friday. Goal is a running engine by Sunday (that takes throttle!). I hate set backs.

Tonight I paint the top end and sand off the fins for that "trick" old skool look (silver edges).

Nissan Pathfinder is now engineless and is getting a crank kit or re-ring job in the next few days. Oldest is doing that one. I looked at the bearings this am and they look rough. Found a leaking rear main seal too.

Jim
 
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GSjimmy
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