engine hours

I know there's no set answer but here I go. Can anyone say what would be too many hours on a engine? I know there are a lot of variables that come into play but was wondering how many would you walk away from. We're still looking for "our" perfect boat but some of the high hours are scaring us. Any opinions would be appreciated.

How many angels can dance on the head of a pin?

What kind of engines are you looking at? How have they been operated? What kind of boat are they in?

No one can answer that question without just a little bit of information. Then, who knows?

David

How many hours are scaring you? 3000?, 5000? 10,000? What do you consider high hours. This has been discussed many times here. It depends on the maintenance the engines have received. Also the HP to displacement ratio of the engines in question. I have 5000 on my Cummins 6BT 210 HP and feel they are just getting broke in. Too many variables to answer your question with a set number.

One Lehman went for decades 24/7 as a ferry, engine was worn out at the end. Likely you won't find that on a pleasure boat. As others have said depends on the maintenance. All of this assumes a diesel engine.

There is no answer. Get a survey by someone very familiar with those engines. A quick red neck screening is to have them started up dead cold and see what kind of smoke they throw off, which is one of the first if not the first things an engine surveyor will do.

Sorry I should have given a little more info …. Ford Lehman 2715E
120 hp
6000 hrs
not sure about maintenance

Not sure how many angels dance on the head of a pin. Must be a trick question.

Might be good, might be bad.

Don't use the hrs as a yardstick. Concentrate on the engine itself and what very experienced people can observe and test. Some people think engines can only make so many revolutions. The real world life expectancy of an engine is usually determined by how much has an engine can take in the form of abuse.

Check and test the engine in the known ways. The way some people treat engines 1000hrs would be too much. 5000hrs would be fine under ideal circumstances or common good maintenance. Compression tests, leakdown tests and oil analysis in addition to observations of a very experienced mechanic. Leaking oil or places that should be clean found found dirty ect. Of course you never know if an engine could have been run w no oil for a brief period of time. I've never seen on YW "forgot to put oil in it once but it's run fine since". Frequently what you need to know is missing information.

500 hours on a 30yo boat would be terrifying and almost certainly a bad idea. 5000 hours on an engine capable of 10,000 might not be a bad choice. I'd look strongly at maintenance records, especially the past 5 years. I want to see use. I don't mind a few things breaking, so long as it is not indicative of a trend or condition. Records without repairs equals deferred maintenance.

Hours are best used to schedule your next oil change. Not much use for gauging engine condition.

ghost said:

Hours are best used to schedule your next oil change. Not much use for gauging engine condition.

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We have an early 1960's vintage Ford tractor used by the grounds staff that shows 6,000+ hours on the meter. The record indicate the hour meter broke in the mid 1980's and the tractor at the time was considered to be in such poor shape as to not warrant the replacement of the hour meter. Here it is 2014 and though we've been threatening to replace it forever, it still chugs along daily.

Last year we completely replaced a diesel with fewer than 800 hours on it... Catastrophic failure. Was a bummer but hey, crap happens.

How a diesel is maintained and used/abused is infinitely more important than an hour meter can indicate. Get a survey and use the perceived "high" hours as a negotiation chip in your favor.

Is the engine well kept or look like its been laying behind a garage for years? Is the boat worth a repower? IMHO most engines die from neglect, mis-use and equipment failures of pumps and heat exchangers than from normal wear.

Bob Smith said in his class that I took that the 120 Lehman starts really coming into its own around 5000 hours. As everyone says, maint., how used really determine the answer but I think the basic motor is solid and if taken care of can go a long way.

I have 5200 hours on mine and it runs great. If you do get the Lehman try and take Bobs class. It's worth it in my opinion.

Jeff

What type (make / model) of boat is the engine in? This would help us determine what load the engine has been subjected to, what life it's lead.

To get between 10,000 - 20,000 hours, you really need to see under 25 HP per liter, and under 2000 RPM. I think the engine you are looking at runs at 46.6 HP/L @ 2500 RPM. This is not bad though, compared to modern engines where they run over 75 HP/L. approaching 2800-3000 RPM. Many High Output engines are trashed below 5000 hours, some a lot less than that, and they tend to suffer a lot of abuse too.

A photo is worth a thousand words. If we could see that, we could advise further. If the boat is well kept / clean / maintenance logs kept up, etc, then no way is the previous owner going to ignore the engines. This is good!

As suggested, you need to get an independent Engine Survey, with compression & oil analysis, etc carried out. It's not rocket science, a professional will know what the score is, no issues.

If it were me I would have the oil sampled. Check by hand if the engine is cold, turn it over and see if it fires immediately and smoothly on all 6 cylinders, all those old Lehman's smoke when cold so take it for a run and get it up to 80/90 degs. Let someone else drive the boat while you check for smoke, and what colour ? then open the throttle wide, it will smoke for maybe 5 mins then start to clear after 10 minutes, now check for smoke, ignore it if it's a wisp of black.
Check engine temps,no more than 100/105 c, now back to cruising speed, lift the floor and check for leaks.
If all OK back to idle and check the engine for 'hunting', if so needs the oil in the injector pump rack changed.
After all that if the boats in great shape you can get overhaul kits cheap as they still make those engines in Turkey.
2 very important point to note on those engines, always keep coolant mixture anti freeze all year round as it keeps the liner seals supple and lubricates the water pump, after a hard run let the engine idle for 5 minutes to relieve the internal thermal stresses before closing down.
Finally there's a great guy in England whose forgotten more about those engines than we'll ever know, he used to race them, his name is Mike Bellamy and his company is Lancingmarine.co.uk , he can still rebuild, or supply new Ford engine and all the spares for them.

I would seriously check everything very carefully before taking the boat up to WOT for 10 minutes. Most Lehman owners don't run their boats at 2500 RPMs too much of the time. If this boat has sat or if the coolers haven't been cleaned or replaced you run a real chance of overheating it and possibly hurting it. I can run mine up for a minute or two but I feel comfortable as I have shot baseline thermals on it, changed the coolers, changed the oil lines to 5/8" lines, checked/changed oils, etc. yes you should be able to hit WOT but if you really like the boat don't blow it up on your test run.

Jeff

This is what multiple oil analysys reports can show, I'm a happy camper. I had gone 247 hrs over 4 months between changes as I was in the Bahamas. This is from Blackstone

--------------------------

TERRY: This is a perfect report for your 120 hp engine! Metals look fine for 247 hours of oil use, with wear
metals holding steady or decreasing compared to the 2/03/14 report. Less wear on a longer oil change
interval is an excellent indication that this engine is running well with no mechanical problems in the works.
No contaminants were found in this oil, and the air and oil filters did a fine job of keeping silicon and​

insolubles under control. This engine's going strong at 6,650 total hours!

Phil Fill said:

Spend the money and have the engine surveyed, couple hundred bucks. 6,000 I would be concern.

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The hours wouldn't concern me nearly as much as the age, which is a measure of the risk that the engine was not properly used and maintained throughout that time. I am of the view that a naturally aspirated engine that is properly maintained and used frequently can easily last 20,000 to 30,000 hours. Some commercial applications are getting that out of QSM 11's (which are relatively high hp and turbo'd).

If the engine can not reach rated WOT Rpm during a brief test do not run it at Wot for any time especially Ten minutes.

A WOT test is intended to see if it is propped correctly, runs properly and doesn't overheat. If all is well only running long enough to see the temp stabilize is sufficient.

When I did the sea trial on my Gulfstar I was purchasing a vessel that sat for 4 years. Step 1 was to contact a tank and fuel polishing company. The top plate on the tank was removed, the dip tubes were removed and cleaned, the tank was cleaned and they were able to visually inspect most of the tank because the plate was removed. It was determined that the fuel was no longer fuel I'd want to run in any diesel engine. 180 gallons were removed and properly disposed of by the tank cleaning vendor. About 50 gallons of fresh fuel was delivered to the boat for the sea trial.
Step 2 hire a Perkins certified diesel mechanic to ready the engines from their 4 year nap. All fuel filters were removed and replaced. All coolant was removed and replaced. All 3 engines (2) 4-154M's and the Westerbeeke 3 cylinder diesel had new oil and oil filters replaced. The previous owners had replaced 95% of the older hoses and V belts 4 years ago. I ended up having to replace 1 alternator belt and the main fuel fill and the tank's vent line. They were cracked and showing signs of their age.
Step 3 repair the Genset it wouldn't start it would try and then stall. This ended up being a bad oil pressure sender. It was replaced the generator now starts immediately and doesn't have excessive smoke.
Step 4 rebuild all the Sherwood raw water pumps. The original owners had replaced all the raw water pumps with Sherwood pumps about 6 years ago. The impellers were changed on all 3 engines. All fresh water strainer filters were inspected and cleaned.
Step 5 after the engines were started check temperatures with an IR gun and compare them to the gauges. All 3 engines were within spec after we ran the boat for about 10 minutes. The WOT run was done by the broker for a period of time between 8 to 10 minutes, I wasn't happy about this and the engines were backed down to normal cruising speeds. There was some black smoke for about a minute or two then it cleared up. Both Perkins engines started almost immediately and there was very little visible smoke. She fired right away and considering the time of layup I was surprised how little smoke appeared. The raw water flow was excellent. The engines are original and have about 2,000 hours on them. The Genset was replaced about 8 years ago. All engines showed good oil pressure well within limits towards the higher end of the accepted levels.
Step 6 the boats been on the hard since the sea trial. It's having the rudder blistering issue resolved, the rudders were removed and new rudder bearings were installed along with the glass repairs. I had the boat's hull or bottom anti foul painted black. A few minor repairs were done before the new black bottom was painted.
Right now the marina is performing some minor repairs stuff I would normally handle but given the distance and my current workload it's better the marina do these repairs in preparation for launching her either late this week or after the 4th of July.
I was fortunate that I had owners that would allow me to do this work based on a fairly low ball offer and a contract contingent on a satisfactory sea trial and survey.
Yes I spent money most would prefer to spends after they own a vessel not before the sale went through. In the end this seems to have worked out well for me because there are very few unknowns for a boat that's almost 40 years old.
Bill

Most of the engine's are run at a gentle 1500 or similar cruising speed. Whilst it may feel good to be 'kind' to the engine what in fact is happening is that because the engine doesn't reach it's correct operating temperature a tiny portion of fuel is unburnt and is put into the exhaust system and creates a black oily coating on the inside of the exhaust manifold and piping. When the engine is gently opened up to WOT (monitoring for any overheating) the engine gets up to full temperature and the unburnt fuel coating also begins to heat up and starts to smoke. As the engine runs hard this oily coating will be burnt off and show itself as blue smoke, when the exhaust system is clean the smoke will clear and the engine will run sweet.
Older two stroke engines were very susceptible to this with a significant drop in performance until they become so poor that action is required either in the form of a costly strip down or, fill the tank with a 50/50 mix of Parrafin and diesel, as Parrafin burns hotter this helps the cleaning, the engine is run up under load (just like your Lehman) and run hard until it runs clear.
What is very important during this exercise, as stated previously, is that the engine is allowed to cool down naturally by letting the engine tickover until the temperature drops to around 70' Celsius to relief thermal stressing.

gonesailing13 said:

Sorry I should have given a little more info …. Ford Lehman 2715E
120 hp
6000 hrs
not sure about maintenance

Not sure how many angels dance on the head of a pin. Must be a trick question.

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Let's assume it was well maintained with meticulous records of service. If you're older than 50...... it will outlive you. 6,000 hours is nothing for a Ford Lehman engine that has been well maintained.

Good Luck!!!

Just as a matter of interest and to put things in perspective we have engines in trucks in the family business, Scania, Iveco and Mercedes and 500,000 miles is normal and apart from normal servicing and things like starters and alternators and we had a Mercedes that exceeded a million miles which worked between Ireland, Sweden as far South as Greece before we traded it so I wouldn't worry about a few hours on the Ford.
The secret is in the servicing, top quality oil and filters, on time every time.

Isn`t another factor in engine life the frequency or otherwise of cold starts. Viz the life of the taxi engine which, despite the usual driver abuse, way exceeds the same engine in the same family car, because the taxi works near 24/7 with multiple drivers, and never gets cold. Much like Irish Rambler`s 1M mile Merc truck. Real "trawlers", and charter/hire boats, achieve high hours too.

BruceK said:

Isn`t another factor in engine life the frequency or otherwise of cold starts. Viz the life of the taxi engine which, despite the usual driver abuse, way exceeds the same engine in the same family car, because the taxi works near 24/7 with multiple drivers, and never gets cold. Much like Irish Rambler`s 1M mile Merc truck. Real "trawlers", and charter/hire boats, achieve high hours too.

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That's one of the benefits of equipping block heaters and using them in all but the heat of summer. And some guys even use them then. As noted above, using your engines and religious maintenance is best of all.

Some people say that a guideline might be how much fuel has gone through it, slowly for many hours, or quickly for not many. It really depends upon how it has been treated.

I wonder how much you have to discount to sell a very good condition 25 to 30 year old trawler with a great running FL 120 with over 6,000 hours , how about 7,500 or more?

The reason the taxi engine's and trucks do big miles as was mentioned in an earlier posts is because when an engine starts from cold the during the warming up period the engine produces sulphuric acid.
This is the reason you are advised to drive off under light load to help pass this phase and not let the engine tickover to get warm, same with a boat, drive off gently until it's warm or if you want to charge batteries from the main engine secure your boat firmly to the dock and put it in gear to around 1,000 rpm to help it warm up quickly, it also helps to burn all the fuel injected because if it runs to cold any unburnt fuel washes the lube oil of the cylinder walls and accelerates engine wear.
If you dip a little oil on your finger tip to taste it will taste acidic if the oil is overdue for changing for this reason.
Many police cars in America are left running 24/7 and an exhaust will last for years as there's no sulphuric acid getting into the mild steel exhaust system.
I hope this explanation helps.