Deleted.

Here are my concerns, the plate filter did not catch all the small metal fragments and it is very likely that they are imbedded in the rod, main and cam bearings, if the engine is pulled down now you may be able to avoid a much more expensive repair in the near future, or is the owner planning to sell it and pass these problems off to an unsuspecting buyer? Either way the safest thing to do is a tear down and inspection. I’m no IA or A&P, just an old gear head and Franklin flyer.

Delteted, sorry to do this. Wanted some advice and opions that it turns out I really didn't want of need.

Might want to post this question to the Stinson group on Yahoo; lots of Franklin experience there too.

The owner's gonna do what he's gonna do. If you're worried about liability, you can do the work the owner wants, and log it, but have the IA do the return to service sign-off. Perhaps note on your work order that you do NOT recommend returning the engine to service without a teardown inspection. That won't make you feel a whole lot better if it fails in flight, but at least it will CYA.

The failure made enough metal to plug the filter, and they don't want to tear down the motor and clean the whole thing?...

You have got to be fuckin kiddin me ........................

hotrod150 wrote:The owner's gonna do what he's gonna do. If you're worried about liability, you can do the work the owner wants, and log it, but have the IA do the return to service sign-off. Perhaps note on your work order that you do NOT recommend returning the engine to service without a teardown inspection. That won't make you feel a whole lot better if it fails in flight, but at least it will CYA.

If that engine fails on a new, unsuspecting owner, I don't think I'd want my name on ANY part of the engine log without showing a teardown.

Gump

Unless there is something unique about the oil path in the Franklin, the route is from the oil pan to the pump, through the mains,the rod bearings, cam bearings but then is filtered as the LAST step before being returned to the pan. All of the above have already had filings passed through them before collecting metal in the filter. If you were only doing engine oil analysis and the report showed heavy metal, what would your mechanic recommend?

Don't know anything about Franklins, is that really the oil path? Seems like a recipe for disaster to filter the oil after it has gone through all the bearings.

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dirtstrip wrote:Unless there is something unique about the oil path in the Franklin, the route is from the oil pan to the pump, through the mains,the rod bearings, cam bearings but then is filtered as the LAST step before being returned to the pan. All of the above have already had filings passed through them before collecting metal in the filter. If you were only doing engine oil analysis and the report showed heavy metal, what would your mechanic recommend?

Hmmm..

Most motors pull oil from the pan, pressurize it with the oil pump, send it through the oil filter and then pipe it back to the main oil galley to be distributed through out the motor... If you went to the bearings first, how would you recover it to send it to the filter???

dirtstrip wrote:Unless there is something unique about the oil path in the Franklin, the route is from the oil pan to the pump, through the mains,the rod bearings, cam bearings but then is filtered as the LAST step before being returned to the pan. All of the above have already had filings passed through them before collecting metal in the filter. If you were only doing engine oil analysis and the report showed heavy metal, what would your mechanic recommend?

I am about to start an argument with myself. I am unable to find the oil flow chart for a Franklin online. I did find one for a Continental. If this is the way the Franklin is then oil from the pump goes first to the filter NOT the bearings. That would mean that the filter would pick up metal first as long as the bypass circuit remains closed. Metal contamination through the oil path to bearings would not happen in the order I posted above. I posted based on my experience with other engines, non aircraft, I have worked on and assumed a common oil path. That may not be so. Ask the oil path question of the mechanic anyway and also the one about oil analysis. Running that engine with just a flushing would still give me pause.

dirtstrip wrote:

dirtstrip wrote:Unless there is something unique about the oil path in the Franklin, the route is from the oil pan to the pump, through the mains,the rod bearings, cam bearings but then is filtered as the LAST step before being returned to the pan. All of the above have already had filings passed through them before collecting metal in the filter. If you were only doing engine oil analysis and the report showed heavy metal, what would your mechanic recommend?

I am about to start an argument with myself. I am unable to find the oil flow chart for a Franklin online. I did find one for a Continental. If this is the way the Franklin is then oil from the pump goes first to the filter NOT the bearings. That would mean that the filter would pick up metal first as long as the bypass circuit remains closed. Metal contamination through the oil path to bearings would not happen in the order I posted above. I posted based on my experience with other engines, non aircraft, I have worked on and assumed a common oil path. That may not be so. Ask the oil path question of the mechanic anyway and also the one about oil analysis. Running that engine with just a flushing would still give me pause.

Agreed... No OIL filter will remove enough metal with a failure that BAD....

Not directly related to your Franklin failure but the results may be.

A while back I built a 406 Chevy drag race engine for a customer who had it professionally installed by a reputable shop in their home town. After properly pre-lubing the engine it started up with good oil pressure, sounded great and all.
But after a period of time, 5-10 min. the oil pressure went to ZERO! No warning, no nothing!

Drove out to take a look, I removed the distributor and installed a dummy distributor that is used to drive the oil pump with an electric drill. Still no indicated oil pressure on the gauge. Switch gauges,... same thing, nothing! The drill motor had resistance and felt like it was pumping oil but the oil wasn't going anywhere......

The Damn oil filter element had collapsed internally and gotten sucked into and stopped up the filter adapter.

Shit, Kiss my ass!!!

OK,..... This is where I think it does relate to a Franklin or any internal combustion engine for that matter.

Both engines, (the Franklin and Chevy) reportedly ran for a period of time without good oil pressure.

Upon dis-assembly of the Chevy engine the rod and main bearings were "wiped". I use the term "wiped" to describe the metal to metal contact between the crankshaft and bearings due to lack of sufficient oil pressure. This contact, even for a relatively short period of time, was enough to ruin the bearings and require the crank to be reground to the next undersize.

I stood behind my work and made the engine right.

The cause for the Franklin filter stoppage was again not directly related to the crank and bearings. 'But'... the crank, bearings and any other part that relies on clean oil under pressure will be suspect to damage from lack of oil pressure and/or particles of metal getting through and embedding into them.

Even though mine was an automotive application, I don't think a crankshaft and engine bearings care if they are in a car, boat, airplane, lawnmower, etc... WITHOUT ADEQUATE OIL PRESSURE THEY WILL START TO FAIL!!!


Just my .02

Kenny

I just went through this shit with my O-300 and a pull-start gear that shattered, filling the engine with hardened steel. What a f**king mess. Once that genie is out of the bottle, all the flushing in the world isn't gonna put it back. That metal is everywhere, and the only way to fix it is to split the case and rebuild it.

It sucks, but it is what it is.

Gump

Bearing failure, rods and mains

If it is contamination, the bearing first inline from the oil source will be bad.

If it is starvation issue (lack of oil) the bearing farthest from the source will be bad

On high time engines
Usually on the old chevy v8's it is #7
On John Deere inline 6's it is #5

BTDT with mine (catastrophic cylinder loss with metal ingested) stewed and researched, tried to get around it, but finally bit the bullet and overhauled it to service limits for (IIRC) less than $6000.

What Stol said earlier.Tear that engine completely down and clean it properly no excuses!!

Bill

Before condemning what possibly could still be a good engine do a little inspecting first. Luckily, you know what made all the metal and that the filter did it's job. The problem is you don't know if the filter caught all of the metal or if it by-passed and sent dirty oil to the engine. I would look for spots that would collect debris. Good spots would be any area where there is a constriction or a spot for debris to settle out like under the valve cover, in the oil filter bypass valve, in the tappets or at least in the passage to them, and that sort of thing. If you find metal in any of these parts then the filter would have been fully plugged and gone into by-pass and contaminated the bearings. If you don't find anything then change the oil, flush the tank, and do some low power/speed ground runs to see what shows up. Check the oil pressure as it is an indicator to what is going on with the main bearings. If they are chewed up then it will be low.

I think by doing some quick and simple checks that have little risk of damage to the engine or pilot you can get a much better idea of what the engine's condition really is.