mercruiser

[bluewater 1]

hi guys i am a new member and looking for some advise on mercruiser 470s as we are looking to bye a bertram 25fb ,i was speaking to my local boat mechanic and he said they are nothing but trouble ,so looking for a bit more feedback on this subject {bm} if you are reading this your input would be appreiciated as from what i have read you are the man in the know.we currently are running a tabs 610ocean series but not big enough for our overnighters out on the reef with 3 off us would like to spend more time out there so a bertie 25 would be ideal as from what i am reading they are a great bluewater boat

[krazyfisher]

nothing wrong with a 470 as long as they are looked after and the maintenance is done on the cooling system.
good power and good on fuel

[Mrs Ronnie H]

Hi
We owned a cruisecraft with one and would never have another. Nothing but trouble and the maintenance cost is a real issue.The day the boat sailed out of the yard I never gave it another thought.
Have Formosa and Suzi outboard now and wouldn't swap it for the world.

Cheers
Ronnie

[captain rednut]

if you want to buy a reliable 25ft bertram with a diesel on a trailer theres one for sale at sandgate in QLD, contact a member of this forum called (midnight) hes name is myles. (great boat)
cheers jim

[BM]

Hi Bluewater, Mercruisers tend to often get a bad wrap which in my view is most undeserved. The reason people end up with some major repair bills is generally due to neglect and lack of use. Either by that person or the prior owners etc

In my experience the 470's are a fantastic engine. Very powerful for their weight and pretty good on fuel too.

They have some little niggly things that need to be noted but every engine has its issues. The integral stator for charging the batteries can give issues. Often they are retrofitted with a marine alternator setup. A good option but not necessary. The last stator I replaced only cost me about $250. Mercury had obviously dropped the prices of those parts to move them on. The stator won't output the same current as an alternator but it is still up to the task without doubt.

The watercooled regulator can let go in a smokey fashion!!

The closed cooling waterpump (driven off the cam) can sometimes do a seal in the front cover. This is evidenced by coolant dribbling from the weep hole in that area. A little fiddly to repair but not expensive if you can do it yourself.

The distributors get a bit of wear in the shaft/housing over time and can become a little sloppy thus affecting ignition timing slightly. This can be rectified by boring and bushing the dizzy. Some opt also for an electronic module (pertronix).

The earlier model 470's had a 3 inch heat exchanger which functions well as long as its clean, the seawater pump is up to scratch and the exhaust elbow isn't blocked. Later models went to a 4 inch unit which works better overall.

Exhaust elbow blockages would be the major cause of overheat for these engines (or most engines really). Elbow blockage (or partial blockage) usually manifests itself as running fine for a while and then after 10 or so minutes at high speed the temp will gradually keep on climbing.

Temp for these engines usually sits around 1/4 guage and up to half guage when really pushing hard. Any more than this and you have a temp issue.

Oil pressure with a warm engine at 2000rpm is I think 20psi minimum (I need to check that as I cannot accurately recall it off the top of my head). A healthy engine at 2000rpm would be pulling 60psi plus.

Compression around the 150 psi mark. Even numbers are the most important element here.

You need to check for excessive slop in the tiller arm assembly too (common to all older and particularly moored Mercruisers). Whilst looking inside the boat at the tiller arm (where the steering linkage connects) have someone rock the drive unit from side to side. A tiny amount of freeplay is ok but if the drive moves through numerous degrees with no tiller arm movement then the tiller arm will be flogged out. There is a short term repair option but it won't last for a great deal of time. You can pull down the transom assembly and repair it though.

The bellows need to be checked closely for any holes or loose connections. Check power trim operation (from both stations). Crack the drain screws on the lower units and see if any water comes out, or if milky oil comes out. Water ingress obviously means seal issues, be they prop shaft seal leaks or waterpump base seals. Can sometimes be the shift shaft seal but rare.

Check trueness of propshaft when test running the engines (if you can test on the hardstand).

Check that it is reliably shifting in and out of forward and reverse gear when its in the water. Shift issues can develop as components wear. Lower shift cables can also get tight and cause shift/stall issues.

Berty 25's like all bigger boats have a lot going on internally with oodles and oodles of cabling, wires etc. Pay attention to all instruments (both stations) and also the engine start and stop controls on the bridge and trim switches on the bridge. The bridge instruments take a real hit from the salt air and tend to fail a bit and the retaining screws seize up and they can be a right pain to get out without damaging them.

Check the hull whilst on the hardstand for any bad repairs or ozmosis etc. Very uncommon to find ozzy in a Berty due to their construction but it can happen. Check the condition of skin fittings etc whilst its out of the water. Poor toilet fittings often see boats sink on their moorings.

Overall, the 470 series of engines 470/485/488 are excellent performers. They are getting on in age although parts are not a problem and rebuild kits for them are available from the US for about $500 landed (pistons, rings, bearings, gaskets). So rebuilding is an economical proposition too if you find one with dead motors.

Perhaps the most important point is to get someone to inspect it for you if you are not capable. There is too much at stake with bigger boats and if you cannot repair them yourself the costs will blow out very quickly.

Cheers

[PADDLES]

i think bm's last statement is the perfect description for older boats with these motors, if you can do the work yourself then these motors might work out ok but you will probably have to do a fair bit of work to get them up to scratch. parts are cheap from the usa which makes rebuilding them not too bad if you do it yourself.

i don't have these motors but my mate has a boat with 2 of them, he has completely rebuilt one of them and is going to have to look at the second one soon. he does all the work himself and still reckons they're a bit of work.

look for evidence of recent rebuilds and make sure it was done by a mercruiser certified business, if you don't find this and the price is not rock bottom (mate's 26 foot flybridge boat was $30k with these motors as an example) then keep looking i reckon.

[Midnight]

Thanks Jim!

Bluewater,
I just noticed your post, sorry I am of no help re the Mercruisers for you ( I have heard nothing but trouble too from mates that had them, but as BM mentioned mostly from poor set up and lack of maintenance I think)

But I do have B25 with Volvo AQAD41A Turbo diesel (200hp) and Duo-prop leg. It has done 565hr since rebuild, including injector pump and all hang on components. All new drive train and engine mounts late last year also.

Cruise at 18.5kts, 26 flat out. burn around 32-33l/hr t cruise and 6-7l/hr trolling.

I do full days on the shelf Blue Marlin trolling for 225L, 50nm run out and back and troll for 10 hours.

The Bertram 25's are THE best 25 footer around in my view. The petrol ones perform really well, but I have always been scared of petrol inboards, and they can be heavy on the fuel if you want to go fast, like any boat i guess.

PM me if you want any more info re my Berty, it is for sale only to upgrade to a bigger Bertram, I love the boat and will miss it.

Good luck with your new boat search, a Bertram 25 will never disappoint you as a great sea boat, but the mechanical side of things will send you mad if you get the wrong one.

Cheers,
Myles

[bluewater 1]

thanks to all for advise , i will be sure to check into every thing that has been mentioned. again thank you all, midnight i will be in touch

[OPTI]

the 470's are seriously getting long in the tooth now ,a repower would be a better option imop.id be looking at the 26 with v6 sterndrives but even they are getting long in the tooth ,the economical life for the average mercruiser is 10 years imop after that they border line on cheaper to repower than repair.

[bluewater 1]

myles could you send me some photos of your boat as i live in mackay but would be interested in looking over it
regards brian
ps and price to please

[Midnight]

Will do Brian, shoot me an email to mylesweston@bigpond.com

I will take some photos tomorrow and email them to you.

Cheers,
Myles

[Midnight]

Cut and paste from a post on our club website;

"I have a bit of tidying up to do on it before I will advertise it, but if anyone here is interested, give me a call.


1981 Bertram 25. Single Volvo Penta AQAD41a Turbo diesel with Duoprop leg. 530hrs since rebuild, new Turbo, exhaust riser, gearbox, driveshaft and housing, drive plate, circulating pump, full cooling system rebuild, engine mounts in the last year.

Furuno FCV620. Lowrance 7200C plotter. GME 600D VHF with second station. Coursemaster 450 Autopilot( currently u/ s, requires new rudder sensor). Lenco trim tabs.
Reelax Reef Rigger bases, 5.5m poles.
400L diesel capacity. I average 15L/hr for a day on the shelf. 50nm run, troll 10hrs, 50nm run home for around 225L. Burns around 33-35L/hr at 18.5kts, around 7L/hr trolling at 7kts.

Sleeps 3 in comfort, 4 with a swag on the deck. Galley unit.

Storm cover and sun awning for lazy days.

The boat has been kept on a trailer for the last 7 years and is fresh water flushed after every use.
It is anti fouled and I will be re doing it prior to sale, so it can be left in the water.

I love the boat and it has a long history of raising fish. It is a safe and economical entry level game boat"

I will take $40,000 for it as it is, but will want $45,000 once I have fixed her up to be "presented for sale". I have not advertised the boat anywhere as yet. It is priced to sell as I have found a 35 Bertram that I would like to move on.

I will get the photos through to you tomorrow Brian if you can send me your email address.

Cheers,
Myles

[Midnight]

Gday Brian,
I just sent you around 80 meg of hi res photos in numerous emails. I hope it does not crash your email.

let me know if it causes a problem and I will resize the photos and re send

Cheers,
Myles

[BM]

That sounds like a more than reasonable price to me Midnight. The last 25 I sold went for $39,500 back in 2005, with recently rebuilt engines (470's). It was probably a tad too cheap at the time really and should have been about 43K.

I think 40-45K for a diesel 25 is quite good buying.

I reckon a bit more hp would be a good thing though. Increase the top speed and also probably lower the cruise fuel fiures a bit. By way of comparison, a 32 Mustang I repowered with new 5.7 V8's cruised at 3000-3200rpm giving 20 knots and 30ltrs per hour per engine. I don't have any fuel figures for a single 5.7 installation in a 25 unfortunately.

Midnight, did you convert it? And if so what was in it prior and what figures did it do?

Cheers

[siegfried]

excellent post BM as good as it gets Thanks:thumbsup:, MYLES dont do it;D

[johnnytheone]

Dear Bluewater. Mate, The Bertie's a lovely boat, but I wouldn't touch a leg with a forty foot pole. I reckon that is the response you'll get from most people, even those that are fairly handy and do their own work. It's not the motor itself that will give you grief, just all the stuff that hangs of it. I suggest you go for a walk around the hard stand areas of maintenance yards and yacht clubs and see how many stern drive units are missing from their boats. In addition, have a look in the "boats for sale" ads and see how many vessels with stern drives for sale have remarks like "motor just rebuilt" or "leg rebuilt", or words to that effect. No doubt I will cop some flak, but that's my view based on personal experience and lots of observation.
I'd put a pod and outboard on a Bertie for sure. John

[krazyfisher]

johnny

What leg did you have???? and what trouble did you have with it?

I think the reason that you see alot of rebuild legs and engines is that it is very economical to do so and unlike 2/s outboards they are good on fuel so not as much to gain from going to a new style engine.

[PADDLES]

the issue with legs is when they get left in the water, in some cases it's unavoidable but like anything that gets left in seawater, it will fail sooner rather than later. i don't think there's any issue with legs that are on boats pulled out of the water.

[krazyfisher]

Paddles I think that is the whole problem people think about legs and forget that most of them sit in the water all the time. As for the inboards for some reason I dont think they get looked after the same as outboards. Maintenance is the key

[Smithy]

I think in Myles' case by having his sit on a ramp trailer he is going to extend the life of his leg. Unless they are work boats and are used all the time, leg boats that live in the water seem to have numerous problems. I am surprised at the amount of crab boats and line boats working out of Mooloolaba here with Volvo legs but they obviously go allright as they are working them all the time. Rec boats that sit seem to give the issues.

[BM]

"a rolling stone gathers no moss".

Likewise a well used and maintained moored sterndrive will have very few problems.

It's the lack of use that kills any moored boat as you have mentioned Smithy.

[Midnight]

Thanks BM and Smithy,

I agree that the price I have set for my Bertram is cheap, especially considering what else is available for that money, and probably more so, the mechanical condition of my boat.

I am going to take a fair old hit at that price, but I had no intention of selling the boat this soon and I have to have it in A1 mechanical condition due to where and how I normally fish.

This is my first sterndrive boat, but owning it has certainly not put me off having another in the future. There are many advantages to the set up, and well maintained and regularly used they can be very reliable.

If I get another sterndrive boat it would most likely be another B25 with Yanmar ZT350 drive, or if Volvo have sorted the issues with their D series engines, a Volvo with a DPH drive with the big nibral props.

Outboard conversions on B25's rarely turn out any good, unless you turn them into a centre console and put a lot of weight back in down low.

I love my Bertram and it is perfect for the fishing I do around here. Sure it is no rocket ship, but at 18-19kts cruise, it is a very rare day that I have to slow down. Going faster only costs more money. These hulls are much happier at 21kts and up, but you need close to 300hp to cruise there.


BM, the conversion was done a long time ago, and you can find evidence of it ever having the twin petrols other than the second thru hull skin fitting for the raw water, and the original placards regarding running the blowers.

It is a great boat, and I will miss it. I just hope it goes to someone who will use it in anger!

Cheers,
Myles

[PADDLES]

i always reckon it's best to buy a boat from someone who uses it all the time, not only will everything be moving and not seized up or inoperable. but usually everything will be working properly because people who use there boat all the time rarely tolerate equipment that is unserviceable and generally fix stuff as soon as it breaks. too many people just look at the hour meter and say "nah, she's stuffed with that many hours"

I wouldn't go so far as to say myles' berty was a "rock bottom price" for a 30 year old boat but it's certainly very reasonably priced for something that (considering his usage) has to be maintained in tippy top condition, it'd be an awesome boat and a very good buy with a ramp trailer included, especially with it being stored out of the water.

19 knots is a nice comfy cruising speed i reckon, hopefully you won't spill your drink hitting waves at that speed.

[siegfried]

Bertram+pod=no good ,simple as that, I have a setup like Myles in 233 and you will not find a better performing (no rocket) economical setup,my fuel burn is less than a barcrusher560 with a 140 4 stk. if you can keep a DP290 leg out of the drink and use and maintain em regularly happy days.Both these boats wre dsighned from the ground up with inbourd installationd in mind by somevery smart fullas.

[ScottB]

Hey BM,

Fuel figures for B25 with single 5.7l (Volvo Penta 5.7Gxi and duoprop leg), looking at 3600rpm = 20kn 45l/h 4000rpm = 25kn 60l/h trolling aprox 15l/hour. We do a full day 15nm out and back (not slowly) and 12hours trolling in between for 230l max. Heaps heaps heaps less than our 470's would do (could add more than half again!!!).

We repowered from twin 470's, in 2009. there was always something wrong with them, many of the things you mentioned, Overheating engines, regulator died (smoke is scary at sea) 2 x Stators. cam seals were done before we got it etc etc. At the rate it was costing us, we figured it was going to be cheaper to repower (seriously!!) It is a much better boat now, but one thing to note is that we carry 80kg plus of lead ballast down the back to return it too its marks. Without the ballast it was a real dog, nose heavy and very very flighty (scary).

With the repower now, you would be hard pressed to find a better 25 footer than the B25, ours has been pretty heavily modified (gutted and rebuilt) and is a great boat to fish out of. Diesel would have been great, but the extra price (try 20k plus) when we repowered was not an option. (20k buys a lot of the extra fuel). We will only sell it to move to a bigger boat with twin diesel shafts (or even better pods)

Scott

[BM]

That sounds unusual that you were using so much fuel with your 470's? They are a pretty economical powerplant. Krayzfish might be able to give us his figures for comparison although its a Berty 20 and not a 25.

How do you find the single drive Scott? B25 flys as you would know are a high windage vessel and as such if theres a decent breeze blowing are downright hard to handle in the confines of a marina. Do you have a bow thruster fitted or just cope with the occasional difficulty in moving about?

I agree re the cost of putting a diesel powerplant in on repower (unless its a s/hand reco unit perhaps) as the cost differential is so great that most if not all recreational users would never recoup the extra cost. They need to sharpen up the price of diesel powerplants and then they would sell well into the rec market.

I was looking at the torque/power and fuel graphs for my latest project boat (my own boat) with a big smile on my dial. Its a 20ft centre console with a 75hp turbo diesel Yanmar shaft drive that at 3000rpm burns 10ltrs per hour! :) :)

Cheers

[krazyfisher]

bertram 20 470 = 45kph 30lph
10-12kph 8-10lph