Reliability of a "professionally rebuilt" engine after being seized?

[dbachelor]

I have been looking for a used-but-in-great-shape 40 hp Nissan/Tohatsu. Haven't found many options (most are too old for me to consider fresh and reliable), but I did find one at marine store which has "0 hours on a fresh rebuild." The story is that it came in a couple years back seized up (not sure if it took a salty dip, ran out of oil, or what) and the mechanic put it aside to wait for a suitable doner. Recently, he rebuilt it--new pistons, rings, bearings, gaskets, and the powerhead/carb off of a 50. (Allegedly, everything is the same between these two except for the throat diameter in the carb?) I think I've got that right; I'm trying to remember if he actually bought any new carb parts or if it all came off the 50.

My question is about the long-term reliability of a rebuilt engine like this. This person is apparently an experienced marine mechanic (however the location is not a certified Tohatsu/nissan dealer or service center), but it is hard to verify exactly what that means.

Can anybody offer an account of personal experience with a fully rebuilt motor like this? Did it run great for only the first 100 hours, or did it provide years of reliable service?

Can any mechanics offer advice as to what I should look for on this to make sure it was a job done right; or what parts I should verify were replaced/gone through to make sure it was a thorough job?

Thanks for the help!

 

[rogerwa]

Re: Reliability of a "professionally rebuilt" engine after being seized?

Here is my perspective. I have the experince of having an auto engine rebuilt and frankly it was never the same. The first time they put in a truck crank and it didn't run right. After taking it back they tore it down and found the problem. But my guess is that they did not use new gaskets when reassbling and took other shortcuts. It never was quite the same and eventually it had some serious issues when I traded it in.

My second is with my jetski. I rebuilt that myself and handpicked the parts and was pretty painstaking about how it was done. It has been flawless this year with quite a few hard hours on it.

To answer your question, it comes down to a few things. How good is the rebuilder and did he do a complete by the book job with quality parts? Second what was the cause of the failure. Was the caused determined and rememdied? If not the rebuild will not last long.

If this motor has 0 hours on the rebuild, it is not broken in yet. If you have a catastrophic fail from a rebuild or assembly problem, it should happen fairly early on. If were to buy this I would ensure there is some level of warranty that would see me through the break-in period if not more. If broken in correctly, good quality parts are used, the assembly is done according to spec, and the original problem diagnosed and corrected, this motor could run for a long time.

 

[DECK SWABBER 58]

Re: Reliability of a "professionally rebuilt" engine after being seized?

Are they offering a warranty? You said he is "apparently" experienced.
How long has he been a marine tech? Does he have any formal training?
What is the shop's local reputation? In the automotive world technicians are certified by ASE. Are they a dealer for any particular brand of motor?
If so he may be factory certified in that specific brand, although not Nissan/Tohatsu at least he would have had some formal training.

Hope it helps.

 

[dbachelor]

Re: Reliability of a "professionally rebuilt" engine after being seized?

Are they offering a warranty? You said he is "apparently" experienced.
How long has he been a marine tech? Does he have any formal training?
What is the shop's local reputation? ...
Hope it helps.

good thoughts, thanks. The way I found this motor was by calling the shop across the street, which IS a Tohatsu certified dealer/service center. They told me to try this guy for a used motor, and I talked to them again and asked about his reputation as a mechanic. THEY said he "has years of experience and it's been done right," but my inner skeptic tells me that I don't know these guys either, and the two shops are across the street from each other in a small town and likely the owners are friends! Seems likely that it is a job well done, but of course I want to become as sure as possible before putting my $$$ on the line!

Seems like the next step is to talk to him again politely about his credentials, and find out more in depth what caused this motor to seize and exactly what procedure has been done to fix it. My biggest problem is that *I* have never rebuilt a motor, so it could be pretty easy to fool me!

The other big question is a warranty-- he is not advertising one, but possibly I could negotiate at least a break-in period warranty of some sort. Any recommendations of what terms should be as far as this goes? I certainly can understand him being wary of sending a used motor off with a full warranty to some likely jackass, just as I am wary about buying a motor built by some likely jackass! So, I want to be fair in my expectations and request...

 

[TOHATSU GURU]

Re: Reliability of a "professionally rebuilt" engine after being seized?

No warranty = No faith in his own work.

 

[dbachelor]

Re: Reliability of a "professionally rebuilt" engine after being seized?

No warranty = No faith in his own work.

Well... I can see someone selling a motor with a warranty and getting into trouble because some jackass took it out and didn't follow the break-in procedure etc, then he is out personal cash and time... Since it is used, obviously the manufacturer is not going to back it, and individuals have limited resources to blow on that kind loss to negligence.

I think I would be extremely careful offering warranties if I was a mechanic... and not JUST because I don't have faith in my own work!!

 

[DECK SWABBER 58]

Re: Reliability of a "professionally rebuilt" engine after being seized?

If their is not a warranty of any kind I would pass. Not saying that's what you should do. If he is good at what he does I would be surprised if he doesn't "stand behind his work". As far as taking the word of the shop across the street the fact that it is a small town is a plus. The best advertising is word of mouth. Unreputable people won't last long in a small town.

 

[rogerwa]

Re: Reliability of a "professionally rebuilt" engine after being seized?

BTW, you will never know what you have until you get it on the boat and in the water. Even if it runs well on the muffs, it won't indicate how it will run under load. In fact the carb tuning has to be done in the water. So from that point do you want to take the chance and have it mounted only to find that it can't get up out of it own way do to a bad build or some other lurking problem??

I wouldn't .

 

[Sea Rider]

Re: Reliability of a "professionally rebuilt" engine after being seized?

If being a mechanic on your own, offering extended warranty is a double barrel shotgun if boater is a very careles guy, for your peace of mind, how many warranty months do you expect the mechanic will give you being a used & reconstructed motor ? Personally have rebuilt 3 Tohatsu's 30 HP that flipped at sea, were completely seized with sand, well overhaulled with new parts don't see a real difference between a new and a professionally overhaulled to new engine.

Happy Boating

 

[pvanv]

Re: Reliability of a "professionally rebuilt" engine after being seized?

Occasionally we take a used motor in trade. If we have not done any work on them, except to test fire, the warranty is that it doesn't blow up when started. Typically a 30-day warranty. After all, there is no way to control or know how the PO treated the motor.

OTOH, if we have been through the motor, and "certified" it to be "like new", which is the only way our shop would sell a refurbished motor, the warranty is for that first season (only). There is no way to guarantee that a new owner will treat the motor as (s)he should, so extending a warranty on a used motor through the off-season storage period (and into the next season) would be crazy.

Either way, if the mechanic does not offer any guarantee at all, as Elvin noted, the mechanic doesn't have faith in his own work, and neither should you.