Topic: Overheating engine - What next?

[Skonnie Boy]

So after about an hour of idling and being stuck in bumper to bumper traffic, my bike stopped running.  Subsequent attempts to kickstart or use the electric starter were of no use, the engine would not even turn over.  The kickstarter wouldn't even budge.  Leaving it at the local Hooters parking lot, I waited about an hour and a half (give or take a few beers) to find that it started right up, first kick.  Obviously, I rode the 2 miles home very slowly.  I'm not surprised it might have overheated since it was 99 here in Austin today but my question is what steps, if any should I take next?  The ride home was uneventful, sounded normal and all that, but I worry that I might have done damage to the pistons or fried the oil.  Thoughts on where to go from here?

Additionally I'd like to take this opportunity to hex the entire R.O.T. bike rally for turning downtown Austin into a parking lot for parade floats, and thus making my predicament even more noticeable to the Legions of Licensed Harley Attire Consumers, none of whom bothered to stop and even ask if I needed help.

Sorry, little tangent there.

[fuzzybutt]

change the oil at the very least. if it were me i'd do a compression check as well.

[HondaMan]

This sounds like the need for new sparkplugs, points AND condensors, at least. The last item there is often overlooked, as folks think they never "wear out". They do, usually they get to where they work poorly when hot.

This is also a symptom of marginal, but still operating, coils. Typically, either the resistors in the plug caps have increased in value with age ("burning open", it's called), are corroded at  their screw-in-point, or the wires from the coils are aged and cracked, which leaks voltage when hot or humid (or wet). This allows the plugs to load up with gas, which makes them stop firing when hot.

Compounding this issue: our modern gasoline has a lower boiling point than the fuels of the 1960s and 1970s. This is due to the EPA's tinkering with recipes, trying to make it burn faster and cleaner: heating it up in the gastank (in hot, heavy traffic) makes the fuel boil in the carbs, which floods the engine and wets the plugs. Then, the engine won't start until some of the fuel dries away. My 1960s-era Fords (with carbs) act the same way in the summer, ever since the early 1980s when this tinkering started.

The 750 was never known for idling well: it just didn't. Mine never did until I built the Transistorized Ignition, which helped a lot. Still, the 500 and (especially) the 350F were the best idlers in this bunch. None of them made good parade bikes: they want to run, instead. 

[mattcb350f]

Good points HM 

What about the fact that he says it seized? I'm guessing piston seizure.

Would a compression test be enough to determine if the cylinders were damaged?

 Matt.

[HondaMan]

Well, if the engine actually stuck, it would have been because pistons #2 and #3 got real angry. It doesn't hurt anything when this happens: I've seen many, many 750s and 500s overheat and stick, only to be fine an hour later, and years later. (Kaw 900s used to do this, too.) My brother's CB500 would do it often in summer, because he insisted on running with his Vetter lowers in place. My 750 did it in an Arizona August once (lowers in place, 2-up riding 100+ MPH, stopped for gas in a small town, couldn't turn it over for 30 minutes), but both of these bikes, on subsequent teardowns, didn't even show scratches on the pistons. And, both of these particular bikes went well over 50,000 additional miles before those teardowns, no problems.

I think Honda thought of this before we did. 

[mattcb350f]

I think Honda thought of this before we did. 

 

Good stuff, and good to know too.

 Matt.

[markjenn]

I'd do an immediate oil change (oil life is halved with each 20-deg increment over optimal which is around 200 deg F), make sure tuning is within specs, and then play it by ear.  Wouldn't be a bad idea to install some sort of oil temp gauge to track future temp excursions.

- Mark

[Skonnie Boy]

Funny that spark plugs should come up, just changed them before the ride.  Huh.  Should mention that the bike was converted to electronic ignition some time ago.  Oil change had less than 500 miles on it.

I'll try to take comfort in HondaMan's words.  After all, it did ride home smoothly.  I think my bike might overheat easier than most simply because the engine was bored out, though the details from the PO remain murky.  As well, my bike died at an intersection, not at full rev.  If the pistons did seize, they did so at 1500 RPM.  Hopefully not too bad. 

At the very least I will change the oil out tomorrow.  If anything sounds or feels different, I'll go from there.  Been looking for an excuse to tear the head apart anyway...

Thanks for the advice, dunno what I'd do without youse guys.   

[Patrick]

Be careful riding this weekend, Skonnie. Most of these ROT posers only ride those chrome tuna boats about 10 miles a year, all during ROT. Then the doo rags and shiney new authentic Harley anti-establishment leathers go back in the closet for another year and its back to work at the insurance agency or dental office. I'm in Austin, too.

Patrick

[Skonnie Boy]

Yeah, ROT's not my kind of scene.  A bit shiny and store bought for my taste.  Was kinda funny seeing my parked next to several dozen parade float H-D's, especially since my bike has no tank badges or paint.  Just a beautiful rust patina and about 3 months worth of road dirt and oil!  Rock and Roll....

[Skonnie Boy]

Last question - considering the possibility of engine damage, should I warm the engine up first before the oil change?  Will definitely go with a heavier oil considering the record heat we've been having. 

Also, forgot to mention, I actually have a oil pressure gauge mounted.  It read near zero right when the bike died, likely a result of the oil breaking down.   

[WFO]

Last question - considering the possibility of engine damage, should I warm the engine up first before the oil change?  Will definitely go with a heavier oil considering the record heat we've been having. 

Also, forgot to mention, I actually have a oil pressure gauge mounted.  It read near zero right when the bike died, likely a result of the oil breaking down.   

What kinda oil was it?

[Patrick]

If you lost all pressure there may be more at work just just heat. If it were my bike I would pull the oil pump cover and make sure the screen is clear.

Patrick

[Skonnie Boy]

Oil was Castrol 10W-40.  Gonna go get some oil, see if I can get a new oil filter too for good measure.

I'll pull the screen on the pump, hopefully its clear.

Recommendations on oil?  Maybe I'll just check the FAQ.

[WFO]

Castrol should be just fine that's what i use it's just strange about the pressure drop though.

[Skonnie Boy]

After replacing the oil (20W-50), oil filter and cleaning out the oil pan mesh, I found the following substances/objects in my engine:

-Gravel.

-Black stuff, possibly originating from Satan or other dark forces.  Al Queda, perhaps.

-One (1) dead honeybee, Apis Mellifera

-Remnants of alternator wiring gasket, RIP.

-Jimmy Hoffa's car keys.  Kidding.

-Metal shavings, about 1/16" or so in size.

Would this be a reliable indicator of a damaged piston?  Ran the bike for a couple of minutes, sounded not too unlike it did before.  A bit tinny around the 3rd and 4th cylinder, but it may have been the power of suggestion.  What does a damaged piston sound like, anyway?  Bike seemed to run strong, whatever that means.

[Hush]

Damn you  Skonnie Boy, hot coffee inhaled up the nostrils is painful, but you have an awfully dry wit.
How long you owned the bike?
Mine came to me from a guy who thought he knew waht he was doing yet when I dropped the sump off there was 1/4 inch of black shet like resin on the sump floor and the strainer suction thingy was so gummed up I'm sure nothing was getting drwn up to the rockers.
I think all Hondas have a random chunk of metal placed in them by some smart-arse jap at the end of the production line to scare us owners.

[Skonnie Boy]

I've had the bike for a year a half.  Running for about 9 of those months.

Just trying to avoid what legendary went through:

http://forums.sohc4.net/index.php?topic=29364.0

Still, with my unemployment benefits coming and lots of time on my hands, I might just be up for a rebuild.  I'LL DO IT, I SWEAR, WATCH ME.

Seriously, perhaps a compression test might diagnose a damaged piston, yes?  Thoughts?

The PO had the bike for all of 1 month before he flipped it to me.  He got it from a dealer, if you can believe that.  I suspect the dealer is to blame for many of my problems, like the crappy powder coating, sh*tty wiring, honeybee in the oil and the recent North American economic downturn in general.  Dicks.

Whatever, I love my bike more than 10 Super Bowls where all the teams win.  So there.

[HondaMan]

A compression check won't hurt anything and might yield a clue as to the sealing ability of the existing rings.
What color is the metal that you found? If you do have a damaged piston skirt (from some previous incident: this one would not have caused this situation), by now it will have possibly scratched the cylinder wall on that one, which means you will have low compression in that cylinder from leakage past the rings. If you find one cylinder low, squirt about a tablespoon of oil into that cylinder and test it again. If the compression jumps way up then, those rings are damaged. If it doesn't change, the valves in that cylinder are leaking.

Reasoning: if the valves are leaking, a PO may have seriously overrevved it at some point, hitting pistons and valves, which can shock off a piece of the piston, usually on the intake side. This is the side where the lowest forces exist during power stroke, so the engine often runs for a long time afterward with no significant ring damage. If, on the other hand, the exhaust side got chipped, the cylinder wall will score up pretty quickly and damage those rings. The exhaust-side breakage usually comes from poor lubrication (or too-light oil, like 10w40 in summertime) over a long time period, combined with abusive practices like a showoff might do: start the bike at the local Steak-n-Shake and immediately rev to redline to impress one's self.

The only other exhaust-side piston failures I have seen (with stock-sized pistons) came from racing situations like roadracing, where the engine is at the limit of lube and stress for long periods of time. These engines are just 'way overbuilt for normal riding, so it takes quite a bit to tear one up!

If the bike has a big-bore kit, the story changes considerably: lube is everything when running those pistons. Overly long oil changes, 10w40 oils (or less) or cheap oils can cause more problems with those kits. If it is a big-bore, you may well be facing a trip inside the engine...

[Skonnie Boy]

The pieces of metal I found were rather like shavings, flat and light in color.  Like I said, they were about 1/16" or less in size. 

PO was vague about the big bore kit, but it surely could be a 836cc kit.  The oil had only about 800 miles on it and was topped off.  It was 10W-40, but its got 20W-50 now.   

I've never done anything resembling burnouts in a Burger King parking, but of course its previous life might have featured guys named Seth with sharktooth pendants popping wheelies for chicks, so what do I know. 

Looks like I'll check compression and go from there.  Big ol' smooch to you all for weighing in and helping me out.  Don't know how I can repay you guys, except maybe by not actually giving any of you a smooch of any sort.  I'll do that, then. 

[HondaMan]

The pieces of metal I found were rather like shavings, flat and light in color.  Like I said, they were about 1/16" or less in size. 

PO was vague about the big bore kit, but it surely could be a 836cc kit.  The oil had only about 800 miles on it and was topped off.  It was 10W-40, but its got 20W-50 now.   

I've never done anything resembling burnouts in a Burger King parking, but of course its previous life might have featured guys named Seth with sharktooth pendants popping wheelies for chicks, so what do I know. 

Looks like I'll check compression and go from there.  Big ol' smooch to you all for weighing in and helping me out.  Don't know how I can repay you guys, except maybe by not actually giving any of you a smooch of any sort.  I'll do that, then. 

Works for me. 

[hymodyne]

..I'm a Rotella T fan, but lets not get into that.
I use a painters strainer in my funnel to catch debris when I change the oil.

I made a mistake with a fuel system cleaner in my tank last season that created problems with overheating that had never existed before and that I haven't experienced since.

On this last rebuild I have been running the lower  fairing in the avatar and things are good so far. in town traffic increases the smoking at start and slow down, but on the road or highway  I have to throttle up aggressively to induce white oil smoke.

hym

[Skonnie Boy]

So I ran a dry, cold compression test.  I found, in cylinder order 4-3-2-1:

165  150  150  150

I'm guessing the overheating episode didn't do any significant damage.  Now I just have to correct a persistent misfire, no doubt the result of cylinder 4 judging by the gas on the spark plug.  Plus, maybe a little tappet adjustment and soon I'll be quaffing PBR at Lovejoy's in no time. 

Thanks for all the advice, guys.

Case closed for now.