what to look for when buying a a/c motor

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wildman9
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Re: what to look for when buying a a/c motor

Post by wildman9 » Wed Oct 21, 2015 9:20 pm

Rainwater my rant wasn't so much directed at you as it was the others just jumping to conclusions when they didn't know any of the facts and hadn't even seen the ad nor what I was asking for it. And I don't have a problem with anyone asking questions to me about something that I'm selling nor do I have a problem with someone giving them good sound advice and facts as related to the motor and what to look for. the problem I have is the ones that just run off at the mouth more less saying its a scam and I'm trying to screw him over with the comments about run away from it and all the other bs. It was known from the get go that the motor wasn't on the boat and was not able to be started up as anyone could've seen from the ad so anyone that was interested in it knew that up front.but what did bother me rainwater was evidently you're not a man of your word when you told me you was coming with the money and then back out of the deal.

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Planeguy
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Re: what to look for when buying a a/c motor

Post by Planeguy » Wed Oct 21, 2015 11:27 pm

Deano wrote:
Planeguy wrote:What are you calling a "pile"? I can go out to an IO-360 on the local airport right now and pull 3 washers and the owner and I have been talking about adding a couple more to bring oil pressure up to the top of the green arc on the indicator. Nothing wrong with his engine. He just wants his pressure on the high side of the acceptable range which is a very good idea.
I see your point about 'a pile' being a subjective measurement. I'm not an AC mechanic, nor do I pretend to be.
I have seen this scenario more than once, so the concern is a valid one. I am more than ready to expand my knowledge in this regard and have open ears. I am aware that the spring can be shimmed and is a standard practice in cases such as you site (where the bottom end and bearing condition is as it should be). Is there a means by which a layman can determine what amount of shimming is excessive and constitutes a justifiable concern?

Is it safe to assume that the washers to which you refer are measured in thousandths? And if so, is there then a predetermined number of them that are allowable?

While shimming the spring increases the pressure on the gauge, there is a point of no return where excessive bearing wear will prevent minimal hot oil pressure on the crank regardless of what the gauge reads cold. This is the scenario that a man would seek to avoid when unable to run an engine to operating temp.

In one case, I intended to add a shim or two to up the existing pressure on a used engine, only to find during the process that it already had seven washers and a nut shimming the spring. That, I would call 'a pile'. :dontknow:
The correct answer to the number of washers is to look in a manual to determine which regulator is installed and go from there. If I remember correctly, it is just a standard number 10 washer (Lycoming part number STD-425) but I would have to go pull one to measure the thickness. I do remember thinking they looked like a typical AN460 washer and those are 0.062 inches thick. Up to 9 washers are allowed in the regulator without a spacer. A maximum of 3 washers if "the" spacer is used. I haven't encountered a bad one. I assume that is because when an engine is overhauled to aviation standards, what doesn't get measured, inspected and repaired or replaced is on the mandatory replacement list. Having said that, seats can wear and trash can get caught in the valve.

I would call your example a "pile" too.

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GeeLeDouche
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Re: what to look for when buying a a/c motor

Post by GeeLeDouche » Thu Oct 22, 2015 2:26 pm

Agreed.

Rule #1- never buy a AC motor without a leakdown and compression test unless its priced so cheaply that you can gamble on it and if it needs to be rebuilt, it can be, and still be reasonably priced in the end. especially if you cant run the motor previously to buying it.

Rule #2- Don't deal with a thin skinned, "Im to busy", easily butthurt junk peddler who isn't reasonable. that's a guaranteed way for everybody to get their panties in a twist. apparently "running your mouth" is trying to help a newbie not get taken advantage of. I suggest checking yourself wildman, or you are going to have a long hard road ahead of yourself.
16x8 Utah style hull With a Waterthunder motor W/ 2.3 CH3 reduction swinging a 3 blade 78" R.
&
17-51 Legend craft w/pods pushed by a MB HD7000

midnight rider
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Re: what to look for when buying a a/c motor

Post by midnight rider » Sat Oct 31, 2015 3:20 pm

Since no one on here knows wild man and I actually do and have actually ridden on the boat and know the motor and I also know that he's busy working 16 hour days trying to restore everyone's power so that they can watch all the football games this season I'm going to bat for him and tell y'all that it is a good motor and it is a good deal

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Comanche-pup
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Re: what to look for when buying a a/c motor

Post by Comanche-pup » Sat Oct 31, 2015 3:22 pm

Why is the power out?


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midnight rider
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Re: what to look for when buying a a/c motor

Post by midnight rider » Sat Oct 31, 2015 5:35 pm

Cause we live in fla. lol

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Comanche-pup
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Re: what to look for when buying a a/c motor

Post by Comanche-pup » Sat Oct 31, 2015 7:41 pm

Im asking cause its kinda my field also and wanting to know about all these outages with no storms, haha?


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Hardtail
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Re: what to look for when buying a a/c motor

Post by Hardtail » Sat Oct 31, 2015 9:39 pm

I too agree with don't buy unless you can get a certified AC mechanic to check out the engine and if you have not ever worked on a Lycoming engine, then you will need to buy parts and pay labor to get it restored to being a reliable engine, if you cannot then I TOO say: Run Forest Run... is the best advice, do not buy a pig in a poke, you will be the one who is disappointed, right now the seller seems to me to be very defensive, and in my opinion, this is a tell tale sign, to RUN FOREST RUN... there are better deals out there, do not just assume anyone is honest and willing to give you this great deal, because they are not selling it if it is in perfect condition. At least you are wise enough to ask for help, so take good advice and keep looking, until you find a deal.

Gary S
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Re: what to look for when buying a a/c motor

Post by Gary S » Sun Nov 01, 2015 6:21 am

I still say if price is right sometimes you have to take a chance. You have a complete engine and a prop. Reputation is another thing to consider. If the man is looking to go bigger and his boat looks like it hasn't been rode hard and put up wet. I wouldn't pay $8000 for motor I couldn't hear or had some kind of return understanding. But if I bought one for $4000 or less you know your taking a gamble. But for that kind of money if the case and crank are good there is room for a great engine at a reasonable price. And you don't have to be a certified AC mechanic to work on a air boat engine.

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