Topic: 78 CB 550K motor rebuild

[AlekStooge]

So as I suspected 2 and 3 are running and 1 and 4 are not.

Here is 2

I hope this is just rich and not oil. I suspected I might have previously flooded the engine with all those kicks, before I got the tank on. I'm not sure if this is re-useable but I cleaned it off and flossed it with a towel between the gap. Came right off.


Same plug as above, 3 was the same.

All signs are pointing to ignition but I wouldn't know what to do with that. I'm pretty confident I set it well.

Also the plug wire on 4 is a concern. It just doesn't feel like it sits tight enough. It's too easy to pull it out. Someone told me I can cut it back and twist a strand around the bolt.

[DaveBarbier]

Can you confirm there’s no spark on 1/4 by holding the plug against the case and cranking the motor? I’m assuming you have the C5 installed correctly using their fairly strict guidelines. If the timing is set from tdc on 1/4 then both 1/4 and 2/3 are set automatically.

I’ve never heard of wrapping the wire around the “bolt”. But you can cut like a 1/4” off the plug wire and rethread it on the plug cap screw. Not sure why it would feel easy to pull off if you’re using their supplied new plug wires. You only need to thread the cap on a few turns.

[DaveBarbier]

The C5 site has a good trouble shooting page.

[AlekStooge]

Do you cut the wire with snips? I have some spark plug wire cutter thing I got a while ago. I didn't know the wire threads in I thought it was just pressed into the boot. I got my C5 from a member on the forum.

[DaveBarbier]

Do you cut the wire with snips? I have some spark plug wire cutter thing I got a while ago. I didn't know the wire threads in I thought it was just pressed into the boot. I got my C5 from a member on the forum.

You cut the wire with some sort of tool that has a blade or two. I mean, scissors could work. It just should be a nice clean cut. Don’t use a butter knife or chainsaw.

If you have normal NGK type plug caps with the screw terminal inside then you push and thread the wire on the cap.

[AlekStooge]

https://4into1.com/ngk-spark-plug-ignition-coil-cable-splicer/

I have a splicer. Won't cutting the insulation just shorten the cable, don't I have to strip it back to expose the wire like when working with any other cable. I have friend that can help me with this, if needed.

What do you think of the plugs on 2&3? I set timing with 1&4 at TDC using the piston stop and degree wheel.

[DaveBarbier]

Since you said the plug cap seems easy to pull off the wire, I suggested to cut the whole wire a bit (yes, that will shorten it) just to get to fresh wire to then thread properly back on the screw terminal of the plug cap. Splicing doesn’t have anything to do with this process. This is only if you have the normal plug caps with the screw terminals inside, as I said before. Only you can determine if that’s what you have. There is nothing about stripping the copper wire core back and wrapping it around any “bolt” in this process.

[AlekStooge]

I will try to twist what I have now to thread it in, before I do any cutting.

[AlekStooge]

It screwed in, I didn't have to cut it. Feels nice and snug.

I put power on and I tried to kick a few times holding the spark plug threads on the head and exhaust flanges not spark in 1/4. I tried the same thing on 3 and no spark. I tested continuity on the engine head and it's grounded.

I took my tank off and checked my connections at the coils and 1 was loose. I tried to push and screw that one in. I got it somewhat tight but doesn't feel like the other 3. I also tested continuity across the wire while I had it off and nothing. I pulled 4 off and same thing no continuity. How that work with the coils. I know they are grounded only at TDC, if the timing is on point. Shouldn't they still have continuity?

Last, I noticed this before but I didn't think anything of it because t's beyond my head. I tested continuity from + power on the coil to the "do not remove nut" and I get it on coil 2/3 but not 1/4? Maybe that is it. I never touched the nut with a wrench.

[AlekStooge]

Back at it. I got the bike running on all four. It was loud, I forgot I had the idel screw pretty tight when it was running on two! I posted a thread on sohc4 bikes and went back to school about testing ignitions. Coil 2/3 failed on the primary winding ohm meter measurement and failed dynamic test. I replaced the coils with Dynas. I may replace the module with a Dyna S in the future since I'm hearing C5s are crap apparently.

I have a few small problems. My alternator phase wires broke. I decided to make 3 way latch connection. I'm waiting for the wires to come in. My right side head covers leaking a little bit of oil. When installing it it didn't seem to sit right so I reinstalled it but haven't fired it back up. Last I can't seem to find the shifter spline I fabricated for my rear sets so I haven't shifted through the gears. I make another one the one I made was kinda crappy.

For those who haven't read my whole thread. I still have to get this bike painted, plated, titled etc., this isn't the final tuning. I just want to get it running decently. I'm afraid it may be burning oil. I was a little unsure when I gapped my rings. Plugs are from 1 to 4. 1 and 3 photos were taken yesterday and 2 and 4 today.







I don't know why plug 4 looks so clean. The pipe was hot. I was getting white smoke from the exhaust. That means lean or oil right? Plugs don't indicate lean. This post from previously should be my carb setup, I don't believe I changed anything. http://forums.sohc4.net/index.php/topic,152261.msg1743559.html#msg1743559

[wolf550]

Done, Cycle X had the tach plug. I didn't find starter plugs anywhere. I'll ask on the high performance section. I'm going to check my plugs today to confirm on which cylinders it's firing. I don't know what after that.

I got my starter plug from frank, Member 754 up in Canada.

[AlekStooge]

Thanks! Messaged him.

[AlekStooge]

Ok, the side cover leak is intresting. I took them off and discovered this.


This is the cover that was leaking. I was concerned at the gap I saw when originally installing.

This is the other one, non leaking. I noticed they were different. That reminded me I pulled the leaking one (first photo) off a CB 500 motor because the one on that side was cracked. So I went down to the basement...

Huh? This is the cracked CB 550 one. It looks like the 500 one that is leaking. Ok?

This is the 550 one, installed on the non leaking side. Fits and sits well.

I tried the same cover on the other side. It doesn't sit well and the gap is present. This tells me the covers aren't the problem. I'm at a loss. Anyone else have this problem?

[AlekStooge]

I tried installing the cover on from the 500. I removed the screw underneath. I tried pushing forward on the L-shapped bracket, tried pulling it back, tried leaving it a little loose. I was able to get it to sit flush before screwing it in but it always pushes out when the allen head is installed on the outside. Part 5 is the L shaped bracket.
https://www.cmsnl.com/honda-cb550k-1978-usa_model7222/partslist/E++01.html#.XvvUm5pOmdk

I fired the bike up twice. First time only ran on 1&2 and shut off after a minute. It was leaking oil from that cover. Second time ran for 3 minutes on all 4 until I shut it off. Cover was leaking. There was also a small leak around the oil pan drain plug. Could it be I put too much oil in. I followed the quantity for engine rebuild. I removed the plugs and cylinder 4 hole was smoking. Pipes 1&2 were a little hotter but that makes sense since they ran a little longer. Plugs are from 4-1 moving down.






Could this be just oil burning during break in? I've never built an engine before but I heard that happens.

[Little_Phil]

Usual leak from end covers is from under L brackets. There is a ali crush sealing washer between the bracket and head and plane washer atop bracket. Do not overtighten...easy to strip thread.

[river]

I fought a leak from the cam covers as well on my motor. A good bit was from the crush washer under the L brackets but then I still had issues from where the o rings are. Out of desperation (because my OCD cannot tolerate leaks) I put an o ring in each hole on the head cover and then reinstalled the cam covers and that took care of it. When I installed the cam covers I could feel the additional o rings seat.

And now that I read Phil's comment again, I ditched the alloy crush washers under the L brackets and used copper ones because the others were not sealing.

[AlekStooge]

Usual leak from end covers is from under L brackets. There is a ali crush sealing washer between the bracket and head and plane washer atop bracket. Do not overtighten...easy to strip thread.

Yes, I was looking at that last night. I checked David Silver but he doesn't have the 6.5mm washer. Then I remember my machinest friend gave me some washers for Christmas, he made a big deal about them, I'm like WTF? They are gasket washers and I able to get 6mm to thread on.



I'll try it out. As for the top washer strange size 11mm, I don't think I have those.

River: so you just added an extra o-ring and it worked?

I watch several compression test and leak down videos. Yeah I'm starting to accept that my engine is burning oil and I'll have to dig into it. That's okay. It's how things go sometimes. I don't have my torque wrenches or most of my tools with me, they are 5 hours away at school.

[river]

Yes. I did not have issues with leaks there before my top end rebuild. But I used a different head and an upgraded cover as well. I used new o rings, tried different ones, looked at slightly thicker ones (didn't like how they felt) and finally tried this (I saw someone else did that at some point while searching). I'll also add that I've had some end covers sit pretty snugly while others have a decent gap between them and the cam cover.

[wolf550]

another option for the single bolt washers are Dowty Seal washers or some call bonded seal washers.
they look like washers with an oring on the inside of them.
I had the side cap covers leak even after replacing the washers.
saw a thread about the dowty washers. bought, installed and now the end caps are always dry.

[AlekStooge]

Yes. I did not have issues with leaks there before my top end rebuild.

Neither did I.

I installed the cover with my gasket washers and the cover sat flush (good!). I fired it up for 3 min no leak. Now the other side started leaking. The only thing that changed was me installing the washer on that side as well. I retorqued twice and ran it each time in between. Still leaks! The side with the original leak was still good. I ran the bike one more time and now both sides are leaking again. Can I get break?

Sometimes it looks like it is leaking from the side sometimes it definently is from under. If you look at the picture from before with the washer on the screw. The washer isn't straight. Maybe it needs to sit over night. Maybe I should try different washer, like the Dowty washers.

Other than that base gasket had a slight leak. Wasn't always present when I shut off the bike. Not too worried about it.

[AlekStooge]

Assortment or get 100 from McMaster Carr. They are like 20 min from me. How often do these come in handy on motorcycles?

https://www.mcmaster.com/dowty-washers/

https://www.amazon.com/Hilitchi-180-Pcs-Metric-Bonded-Assortment/dp/B07CKVYWD4/ref=sr_1_3?dchild=1&qid=1593636643&refinements=p_n_feature_eleven_browse-bin%3A3622111011&s=industrial&sr=1-3

[wolf550]

I got a couple packs of 7 on ebay for 8 bucks each.
there is a guy that sells a single metric one for 8 bucks each that was the right size.
bought these a little less than a year ago and never changed them.
I still have 10 left.

The other option is the original washers that I still have for that just in case moment.
I think the originals get molded over the hole where the bolt goes in making a tight seal
I never used them though after buying the dowty washers.

[AlekStooge]

Got the assortment. I found a 5 pack for $7.25 on Ebay. This was a better value.

I'm debating on whether to dig into the top end to see what it going on.

[AlekStooge]

I took off the valve cover last night.


I was concerned about the pucks being so loose when I was installing them. They are a lot more snug.

I don't have compression gauges or a compressor to do a leak down. I either bent a valve due to inexperience during my cam degree or I over gapped the piston rings, yeah I was unsure of that when I was filing them.

Here are the plugs 1-4, bike was upright when running






Anyone care to chime in?

I also looked at my carbs. Cal mentioned to take the 45 pilots out. I must have forgotten to do that. I don't have replacement 42s, just the original which are pretty gnarly. Only one of them is drilled out by the PO. 108 on the mains.

[AlekStooge]

I got a Motion Pro compression guage. I also was looking at a Bikemaster because of more fittings and the schrader is at the plug end. I know consistency across cylinders matters more than accuracy but still I read having the schrader at the plug is better because of less volume. Correct? Read the engine FAQ on this as well.

Any here are the numbers with 59mm Wisecos 10:1

1-195 psi
2-194 psi
3-196 psi
4-195 psi

This is kicking the bike about 20 odd times for each cyclinder. These numbers are the highest I got them to go. I am concerned that it is oil sealing the rings because there is so much in there. Is that possible?