Rebuild or Re-Engine

[Saltyhog]

My 1981 Bayfield B32 is in need of some engine help. The original raw water cooled Yanmar 2QM15 still runs, but it got low compression and so starting her up takes a while (too long) and she won't idle below about 900 RPM. That and the fact that it's leaking oil from several seals means it's time to do something. We are planning on taking this boat down the ICW and to the Bahamas in several years (from the upper Chesapeake), so a reliable engine is high on my list of priorities.
I had been planning on taking my current engine to Mack Boring in NJ and have them rebuild it. But then yesterday I was talking to another sailor at my marina and he said that there are several areas on the ICW where I might be seriously underpowered due to currents. I’m torn between just having this engine rebuilt or replacing it with another larger remanufactured engine. Rebuilding the current engine would be easier and cheaper, but a larger engine would add some safety margin and probably longevity as it would most likely be fresh water cooled. I've seen some rebuilt 3GM30's and 2GM20F's for sale online.

Some questions:
1) Am I under-engined for the ICW and beyond with only 13 HP? The boat displacement is 9600 Lb. and the LWL is 23.5 Ft.
2) The 2QM15 is pretty tight in the engine compartment. If I were to try to go with a 3GM30, I'd likely need to do some cabinet re-work to make it fit, in addition to engine mount alterations. Would all that effort really be worth it? I know the 3 cylinder engines are a lot smoother than the 2 lungers. I also wonder if the 2GM20F would be drop-in.
3) What about fuel efficiency? My fuel tank is only about 12 gallons. I know the newer engines are more efficient, but by how much?
4) Any reccomendations as to a good source for a rebuilt engine (preferably FWC)?

Any advice here would be greatly appreciated. I'm most of the work myself because $$$ is a consideration.

Tom
SV “Luna Sole”

[Pete7]

Tom, I have no experience with the ICW, you will need advice of currents from others on here.

However, we have certainly ploughed our way up and down the Solent and English Channel often enough. We weigh in a tad more, but not much more and a waterline length of 25.4 feet. We have potentially 28 hp but rarely use anything like that. Certainly 13hp sounds a bit light.

What sort of hull speed can you achieve under full throttle? and is there a reason to limit yourself to one make?

Pete

[Saltyhog]

Pete, I'm not sure what full throttle speed is as the boat is new to us. I seem to recall during the sea trial we were at about 5 kts, but it was a choppy day. No need to limit to one make, I just figured another Yanmar might be an easier fit. I've heard that beta marine has a good engine, but I don't how difficult the refit may be.
-Tom

[Artif]

Why worry about longevity, it has lasted 30 years (assuming it's the original engine).
Must admit though 13hp "may" be a bit low but the torque figure may be a more useful figure to compare. And the rev range of the engine obviously.

[joey69]

ICW

[bljones]

A DIY rebuild is ALWAYS cheaper and arguably just as reliable than a repower, with two provisos:
1. You aren't afraid to get your hands dirty
2. The existing block is WORTH rebuilding, ie., not salt corroded/drowned/neglected to the point of being unmachinable/salvageable.

How do you know whether it is worth rebuilding? Tear 'er down, me boy, tear 'er down!

Working on a Yanmar is not rocket surgery- in fact, 75% of the tools in a $79 Craftsman Mechanic's 219 pc. Socket/Wrench set will go unused. Cro-Magnon man could take this engine apart in minutes while muttering "Ugh, this not so tough, why mechanic charge $95 hour?"

Here's the schedule: Monday-Buy a manual. Buy a rebuild kit. Save money by ordering online. The partsand manual should be in your hands by Friday. Tuesday- Have a mechanic do a compression test- psoe questions on CF. Wednesday-using feedback from CF, diagnose the symptoms. Thursday, argue with feedback from CF, clarify advice, offer thanks and promise to post results. Friday, Parts and manual arrive. Read manual and realize CF posters were, as usual, correct. Saturday-Sunday- Cure the problems with the parts in the kit. Keep the rest of the unused parts as spares. Moinday- Have fun.

you're right about engine bay space being tight- Ted Gozzard designed for big-walleted overweight comfort-oriented people, not systems. Work with what you've got and make it work.

[galynd]

I replaced my 1982 3gmd - 20 hp (raw water cooled) engine with a 3gmd30f (29 hp) fresh water coolded. The 3gmd was running excellently but had rusted out along a water jacket, from the inside out. It actually had several pin leaks. The 3gm30f uses maybe 1/3 gal at cruising speed. I looked patiently and found it from a boat yard in Rhode Island for $2k + shipping. I considered some rebuilds but were about twice that amount. My point is I've been told that a raw water engine block will only last about 25 - 30 years, which mine did. Yours is now 30. there are some great deals if you look hard and patiently. However, a friend of mine put a rebuild (2gm20f) into a catalina 30. It's an awesome motor and one I'd trust with my life. Though the power seems plenty in our sailing area I prefer the extra horses of the 3gm30f.

I'd repower with a rebuild if you plan to cruise long distance in the future.

You might take some very accurate measures and look into the specs of the motor you plan to install. Yanmar lists their measurements pretty accurately in their online manuals of older engines. Put the largest rebuild you can put into your engine compartment.

New engines are more compact but you'd probably pay $11K for approx a 20 hp. Rebuilds are just as dependable.

As for a source, I don't remember as I was basically just searching the internet.

Good luck,
greg

[bljones]

oh,one more piece of unsolicited advice- the most important tool you can use during teardown, especially if you are unfamiliar with the engine undergoing surgery, is a camera. Document EVERY step. If you are a novice, or suffer from all the self-confidence of Leonard Hofstadter then every time you remove a nut, bolt, screw, belt, hose, pipe, gasket, part, assembly, or finger from your nose, take a picture. if you have a document of how it came apart, you will be able to put it back together.

[sww914]

Look at the dollars first. It was much much cheaper for me to buy a good used low hours 4.108 than to buy the parts to rebuild a 4.107. I thought it would be the other way around until I looked at it with my calculator.

[Maren]

The horsepower alone isn't the deciding factor; it's more like hp/displacement. So 13 hp for a Searunner 34 is a fine because you're looking at about 8,500 lbs ready to go. Now if you boat is outfitted for cruising at something more like 11,000 lbs (about 40% more) you might be a bit under. I say that with a caveat; namely, skill. A lot of sailors aren't really all that good and this is where you need both an honest assessment of your ability ... and your crew's. To that end, an engine is both a convenience and a crutch. Folks have, and still occasionally do, sail without the benefit of an engine. With respect to the ICW, you should be fine but you won't make a lightning quick passage. There are a few places where currents will be an issue, specifically by some bridges, but overall not too much of a worry since you can just stand off a bit. If you're mechanical, the experience will show you a good deal.

On the other hand, a larger engine will (if everything is balanced) give you some added power (and lifespan as you pointed out) should you need it. You are likely going to want to look at tankage in that case too, if for no other reason than people tend to use what they have.

So read this as a weak endorsement for refitting, assuming the engine is basically sound. Unfortunately, you won't really know until you really dig into it.

[Saltyhog]

Wow! Thanks for the great responses. One of my concerns with rebuilding the existing 2QM15 is that I don't know how badly the block is corroded in side from all those years of saltwater (brackish really in the northern Chesapeake). I know when I remove the hoses from the engine to the hot water heater, they are almost totally plugged with deposits. That's another reason for FWC -- Real Hot Water for the boss. I'd guess that a remanufactured FWC engine is going to be a better long term deal. I guess I'm still a little torn as to which engine I should be looking for: 2GM20F or a 3GM30F or something else altogether. Would a 2GM20F fit in the same space as the 2QM15?

[Noname1]

Originally Posted by bljones

oh,one more piece of unsolicited advice- the most important tool you can use during teardown, especially if you are unfamiliar with the engine undergoing surgery, is a camera. Document EVERY step. If you are a novice, or suffer from all the self-confidence of Leonard Hofstadter then every time you remove a nut, bolt, screw, belt, hose, pipe, gasket, part, assembly, or finger from your nose, take a picture. if you have a document of how it came apart, you will be able to put it back together.

All hale the Wise man. I was doing and engine and during the process was forced into hospital for long overdue surgery. Didn't get back to the project for six months. The fotos save my asterisk! I have even gone so far as to run a video camera in addition to macros with the camera so as not to be trying to do two things at a time and not be tempted to say I don't need a shot of that.... I can just barely do one thing at a time anymore

[never monday]

the QM series if fast becoming extinct. Move up to a GM or even better a YM

[Capt Phil]

In my old, old underpowered 32 foot pocket Ingrid, I replaced the old Farrymann single banger deisel with a 29 Hp Yanmar. There was heaps of room for the changeout but the first trip out I had forgotten to factor in three times the fuel usage and ran out of fuel in a rather awkward spot. After spending about 2-3 hours trouble shooting the problem, I happened to accidently drop a spanner on top of the fuel tank which issued a resounding 'clank'! Dipped the tank, bone dry. Felt like an idiot particularly because I was trying to impress a lovely young lady. Once back at the dock, installed a new fuel tank, about 30 gal, I recall and everything was bells and banjos from then on except the young lady who moved on to a powerboater. Hope this helps... better to make your gross boating and mechanical errors in private... cheers, Capt Phil

[Saltyhog]

Originally Posted by bljones

you're right about engine bay space being tight- Ted Gozzard designed for big-walleted overweight comfort-oriented people, not systems. Work with what you've got and make it work.

Although you are undoubtedly right for a new boat, I can tell you that my wife and I have actually lost weight doing all the refitting, fixing, refinishing, rebedding, etc. that we've had to do with this boat. It's been a real learning experience. We bought the boat to learn about cruising, and since they say cruising is just fixing your boat in exotic locations, I guessing we're half way there. We're fixing our boat, just not in exotic locations . Gozzard's boats may not be the best performers, but they sure are pretty to look at... to my eye anyway.