Hi folks,

I have a bizarre problem with my Honda ATC185S. I just picked up the bike and fixed the CDI and it started right up. It ran a few seconds and the engine seized up. I un- seized the engine by squirting oil down the spark plug hole and rocking the engine back and forth. Once again the engine started right up… and then seized again. This cant be good for the engine.

I checked the oil strainer screen and it was free of debris. Also I removed the pull starter and spark plug and spun the engine over with a drill and socket on the flywheel. I can spin the engine over with out a problem. I had the engine spinning for about 5 min.

I pulled the valve adjustment cover to see if any oil was getting to the top of the engine.. I really cant tell if any oil is getting up there.

How can I verify the oil pump is working?

 

If the sump was full, and you spun the motor in the correct direction, Id think youd see oil in the head by now. Did you spin the motor over in the right direction?
When you say it siezed up...did it stop suddenly, or did it just die?

 

Do you know any history at all regarding this engine? Rebuilt recently? Did you replace the CDI rotor or the CDI box to get it to start?

As for cleaning the screen, it wouldn't have mattered unless it was completely plugged up. The oil filter on these engines are of the mechanical type and it is located on the end of the crankshaft under the right engine case cover. These do stop up after years of use and should be the first thing any new owner of these old trikes should do. It will give you a noticable power gain in some cases because it will raise the oil pressure and if nothing else, you are adding life to the engine.
It amazes me at how many of these trikes see a rebuild every single year and it's mostly all due to no one taking the time to clean the oil filter because they see what it involves and overlook it.

The problem you have does sound oiling related, but where the problem lies could be anything from the pistonpin to the camshaft bushing and everything between. I would first look to see if you are getting oil to the head and if so, I would start looking for either a warped valve causing the problem when reaching operating temprature or a piston pin seizing once it heats up. A piston pin seizing is usually due to a lack of oil at some point. Either a lack of oil pressure or a very low oil level.

And runnning these engines without oil destroys the rotor in the oilpump very quickly, so try and get as much history on this engine as you can and it will help you out alot regarding where to start with your problem.
I hate it when you buy something, and gremlins pop up. When there is no history available, it just makes it that more aggravating and time consuming to the owners. I hope it's not much and you find yourself of the trail soon.

 

Hi again folks,

Wow thanks for the input! Here are a few more clues..

The oil level in the engine was up to normal prior to starting. When I spun the engine over with the drill, I spun it in the direction the pull starter would spin it..counter clockwise.

The history of the engine is unknown, however there appeared to be a nice layer of crud on the outside of the top half… suggesting that the engine had run in its current build configuration. I’ll rule out a over size piston that’s too tight for the bore.

After posting on the forum last night I went back out in the garage and pulled the right side cover to take a peak at the oil pump. There was a slight layer of sludge on the inside of the case. Unfortunately I don’t have a socket deep enough to grab the nut on the primary clutch. (nut was exposed after removing the four screws on the clutch cover)

I’ll pick up a socket today…What direction should I turn the nut on the primary clutch?

More to come…. Please keep sending advice…

Thanks

Jim

 

The nut you are referring to has left hand threads.

You seem to be on track with the inspection. Keep us posted.

When you removed the 3 screws on the oil filter cover [that exposed the nut], was there alot of metal/crud build up in there??

 

Hi again,

Here is the progress so far.

When I removed the oil filter plate there was some sludge on the inside of the cover. There were also some very fine aluminum partials there as well.

It was a all evening event to find a 30mm deep well socket to pull the nut on the primary clutch. Finally got it off…. Now for the next puzzle.

How to get the oil pump out… I pulled the two 8mm bolts out and I turned the crank shaft and discovered that there was a Phillips screw hidden behind a round spinny thing. I assume is part of the oil pump.

I tried to get the Phillips screw to loosen … no luck.

Anyway its cold here in Michigan and I gave up for the evening..

Am I on the right track on getting the oil pump off?... I don’t have a manual, however I have rebuilt about a zillion little Honda engine in the past. Every one of them was different.

Also dose it sound like the oil pump is faulty? There is one on ebay right now… I wonder if I should bid.

I’ll be out of town a few day on business , I’ll continue the project on Friday

Thanks again..

 

Yes, those two phillups scews are what holds the oil pump assembly in place. You will have to rotate the oil pump rotor a bit to align the holes to get access to them ofcourse. Forget taking those screws off with anything but an impact driver though unless they have been removed before. Messing with it without one will really cause you a headache later on.

I don't have a repair manual with me handy at the moment that has the specifications in it, but what you want to check with the oil pump is the clearance between the inner rotor and the rotor body inside the pump itself. If it is even a bit off, your oil pressure will suffer. I will try and post the specs for it tomorrow if no one else gives them to you before then.

A few small particles in that oil filter cover is normal. The way we used to determine an engines overall condition was based off of how much metal was in this cover. I think one teaspoon was the maximum that we went by back then........LOL

 

Hello again,

I finally got the oil pump off the engine…... thanks to a $3.99 Harbor Freight impact driver.

What confused me was the additional aluminum casing that went between the clutch cover and the main engine case. Poor lighting and lack of a manual may be the blame.

Anyway the oil pump came off and I was disappointed to find the pump is in reasonably good condition. I used the specs from a CB175 manual.. certainly not a accurate way to determine true condition, however the pump just didn’t appear screwed up.

I ‘m in the process of locating a gasket kit… I’m thinking I should pull the top half and give it a look. Any suggestions?

Thanks

Jim

 

Hello once again,

I pulled the engine off the chassis and yanked the head. Well I discovered what was locking up. The bearing on the little end of the camshaft is real tight. Probably all messed up inside.

Perhaps it was just a fluke. Starting the engine after such a long dry period wrecked the bearing?

Anyway the timing chain didn’t suffer any damage. Looks like I’ll need a camshaft.

Would anyone have a camshaft they would like to get rid of?

Thanks

Jim

 

A very busy morning on ebay. I scored a complete gasket kit and a ATC head with a camshaft. I’ll probably just use the camshaft and resell the head on ebay.

Anyway while I was cleaning up the various parts in preparation of reassembly, I discovered a possible blockage in the oil delivery.

It would appear that there may have been a blockage on the clutch cover where the crankshaft fits into the cover. I wasn’t aware that there was an oil passage in the cover and it only became clear after soaking the cover in solvent for a few hours.

If I’m lucky I’ll have all the parts to finish the repair by next weekend…