Why did 295cc seize?

[langted]

Thanks RSP. Just a little more persuasion did the trick. And KGSC, 100% on the money!! Seized on big end of fan/flywheel side of the connecting rod. I will try to attach a picture.

New questions:

1) root cause: Low oil? It was on the dipstick on the "add" mark, but not below. I will look over oil delivery parts and passages very closely, but is there an aftermarket oil press gage? Looks to me like this might have saved a lot of fuss.

However...the connecting rod bolts on the bad side were barely over finger tight. The other side took a strong pull to snap them free. could it have been loose, lost fit, and then galled and got TIGHT on the crank? (In this case not an oil problem)

2) The crankshaft grooves will just catch my fingernail. Can I smooth them out and re-use crank as kgsc suggested? how? 400 grit wet/dry?

3) Suggestions for a good source for a new connecting rod and gasket set?

Thanks again.

Ted

[RSP]

Check over oil pump real well, either oil pump is not pumping enough oil or the oil gally plugged up somewhere , somehow. Never seen a loose rod tighten up. Motor stll had plenty of oil in my opinion

[simple man]

Your bolts on the bad rod may have been loose because it got hot and expanded causing the bolts to stretch a bit. Then when it cooled off the rod contracted leaving the bolts loose! I've seen this on a lot of engines with aluminum rods! Follow " RSP's " advice and make sure everything is spotlessly clean on reassembly!

[RSP]

These little engines are a very good little engine, I dont care what anybody says, I have had TONS of them over the last 20 years. Take the cover off the side of the head to get to the oil pump, replace them in my opinion. Make sure your cam on that end of the head does not have play in it thus making the oil pump gears seperate and loose oil pressure. I`ve seen rods melt from debri getting in the oil passages and stopping oil flow. ALWAYS make sure when the dipstick is put back in the engine that no dirt gets on the end of the dipstick, happens all the time......

[gornoman]

GREAT photo!

[rvkersh]

I think dirt made it's way in there and caused the galling, that rod gets oil first, the other rod is perfect. I agree with RSP, check that oil pump over well. When you reassemble it pour oil down the port that feeds the cam, it is direct to the oil pump and will prime it. If you don't have an oil light, take a test light, attach it to the white wire by the coil and the other end to batt. pos. Disable the ignition, turn the motor with the starter to make sure the light goes out and verifies oil pressure. Good luck.

[kgsc]

Better yet, if it doesn't have the oil pressure light, now is the time or install a gauge..

[rusty shackel]

is the cart lifted? and yes i will explain .

rusty

[big mule]

Originally Posted by langted

Thanks RSP. Just a little more persuasion did the trick. And KGSC, 100% on the money!! Seized on big end of fan/flywheel side of the connecting rod. I will try to attach a picture.

New questions:

1) root cause: Low oil? It was on the dipstick on the "add" mark, but not below. I will look over oil delivery parts and passages very closely, but is there an aftermarket oil press gage? Looks to me like this might have saved a lot of fuss.

However...the connecting rod bolts on the bad side were barely over finger tight. The other side took a strong pull to snap them free. could it have been loose, lost fit, and then galled and got TIGHT on the crank? (In this case not an oil problem)

2) The crankshaft grooves will just catch my fingernail. Can I smooth them out and re-use crank as kgsc suggested? how? 400 grit wet/dry?

3) Suggestions for a good source for a new connecting rod and gasket set?

Thanks again.

Ted

The "grooves" on your crankshaft are most likely aluminum from the rod and can be removed by CAREFULLY using muratic acid.Forgive me if this has already been mentioned and overlooked by me.


.

[langted]

First, thanks one and all! and I like the loose con rod bolts explanation. Makes sense.

--OK, Rusty, I'll bite. The cart is not yet lifted, but will be. Why??????

--The filter screen was in place. How would large enough particles get by? Is the fit of the screen to the pump suction that loose? However, I have to say, the oil was black, way worse than I would like it to be.

--There is no oil pressure light, no sender/pressure switch, no gauge. Is there one I can purchase? It looks like there is a threaded plug in a passage from the pump that would be an easy location to tap in. If nothing is actually available, does anyone know the normal running pressure at pump discharge so I know what range swithch/gage to rig up?

-- Most important right now: A few have mentioned using muriatic (i.e. hydrochloric) acid to clean the crank. I know aluminum is much more active than steel, so it would be attacked by the acid faster than the steel. Still.... the steel would be attacked. So there must be some technique involved. What would that be? Blot it on with a cloth? For example, you certainly don't want to leave the crankshaft in a vat of acid overnight.

--Mule: I'll try to remember you both, but especially that other guy!! "For what does it profit a man to gain an EZGO and forfeit his soul?" (Mark 8:36)

Ted