What gearbox for an HR2

[RobbieTee]

Gents - i am the MD for the PRM Marine business. If you call 02476 617141 and ask for Martin Harris our tech manager he will answer any quations you may have about our PRM150 and 260 and if you want to buy one i am sure we could come to some sort of deal. Rob

[Guzziman]

Gents - i am the MD for the PRM Marine business. If you call 02476 617141 and ask for Martin Harris our tech manager he will answer any quations you may have about our PRM150 and 260 and if you want to buy one i am sure we could come to some sort of deal. Rob

 

 

I hope your new venture is "very" successful as we have a new 260 waiting to be used by us (boat not completed yet) and sometime in the future, many years I hope, we will need your parts/service back up.

 

best of luck,

 

regards,

 

Guzziman

[casper ghost]

We're still messing with this HR2. Got to change the governor and fit a throttle.

We've noticed that when the clutch is removed the take off from the engine turns at half the revs of the flywheel, so there must be a 2 to 1 reduction in the engine, is this normal? I wanted to fit the gearbox here but that would make it 4 to 1 reduction.

If the above is trouble, can we just fit the gearbox to the starting shaft which comes off the flywheel so the engine is the wrong way around.

[OptedOut]

Yep, quite normal, the box takes its drive from the camshaft.

The pic of my engine is the wrong way around. Lister Blackstone box fits where your reduction box fits.

Study the pic and try to find a suitable bell houseing.

Edited November 13, 2008 by OptedOut

[casper ghost]

Yep, quite normal, the box takes its drive from the camshaft.

 

 

Did you fit bell housing on flywheel end then on your HA2?

The 2 to 1 reduction on my engine, i will need to remove that then before fitting gearbox, if I use that end.

[OptedOut]

If I understand correctly you will need to remove the current reduction gearbox and replace it with a gear train cover similar to the one in the pic below (cast iron or steel).

I think you will have to get an extension shaft to go with the cover.

 

You then need to find a pump type bell houseing and machine it to take the gearbox register spigot and drill bolt holes to suit, as per pic below.

 

You will also need to make up a spacer of some sort to adapt from the three bolt flywheel extension shaft to a flex drive plate, in my case just a bit of 11 inch cast iron bar machined with alternator belt grooves and a flat face for the drive plate. You can just see the drive plate adaptor in this pic.

You may also need a starter ring if one is not fitted.

 

You may be able to make something simpler if you fix a disc to the shaft and drive the alternator off the other end of the engine.

 

This gentleman has a lot of experience with Listers.

http://www.marineengine.co.uk/

[Timleech]

Yep, quite normal, the box takes its drive from the camshaft.

The pic of my engine is the wrong way around. Lister Blackstone box fits where your reduction box fits.

Study the pic and try to find a suitable bell houseing.

 

That could be a bit confusing. The Blackstone box takes its drive from the crankshaft, not the camshaft. If you want to fit a marine box onto that end, you will need a cast iron timing case (a lot of industrial H series engines had a pressed steel case) as well as a stub shaft to bolt onto the end of the crankshaft. If the extended camshaft is in the way it could just be cut off (once you are absolutely sure what you're doing )

The alternative, (possibly simpler if you're not using a Blackstone box) is to do something along the lines that OO has suggested, with the box on the other end. In that case, you'll need a cast flywheel housing, some of those were pressed steel!

 

Tim

Edited November 13, 2008 by Timleech

[casper ghost]

Yes, i must admit i'm leaning strongly towards fitting the gearbox onto the end with the flywheel. I can easily make safe the other end. I'll prob make a housing myself fitting a pulley between engine and gearbox similar to picture.

I'm toying with the idea of fitting a dynastart so i can start with a pulley and belt off the shaft rather than having to fit a ring onto the flywheel and use a starter motor, i'll still need to fit an alternator but a bouble pulley will achieve this.

Theres a dynastart for sale which says its suited to a volvo DM2 engine, approx 17hp, I wonder if this would start an HR2?

[OptedOut]

That could be a bit confusing. The Blackstone box takes its drive from the crankshaft, not the camshaft. If you want to fit a marine box onto that end, you will need a cast iron timing case (a lot of industrial H series engines had a pressed steel case) as well as a stub shaft to bolt onto the end of the crankshaft. If the extended camshaft is in the way it could just be cut off (once you are absolutely sure what you're doing )

The alternative, possibly simpler if you're not using a Blackstone box) is to do something along the lines that OO has suggested, with the box on the other end. In that case, you'll need a cast flywheel housing, some of those were pressed steel!

 

Tim

 

You're right, I was making assumptions on the Blackstone box based on the reduction box set-up.

Fortunately my engine had the cast fan shroud.

[casper ghost]

Back on this issue again. Buying a starter motor for the HR2. We can get a fairly cheap one but it isn't insulated from the engine so it normally earths through the engine, though it does have a terminal on the starter for the earth. Or we can pay loads more for an isolated starter which is insulated from the engine. Does this really make any difference. The starter is only on for a short time. I know someone who has a car alternator on their engine, which is presumably not isolated from the engine and on all the time.

[Timleech]

Back on this issue again. Buying a starter motor for the HR2. We can get a fairly cheap one but it isn't insulated from the engine so it normally earths through the engine, though it does have a terminal on the starter for the earth. Or we can pay loads more for an isolated starter which is insulated from the engine. Does this really make any difference. The starter is only on for a short time. I know someone who has a car alternator on their engine, which is presumably not isolated from the engine and on all the time.

 

Listers used to fit isolated return starters & alternators as standard to their marine engines. Current practice with most makers is not to bother.

Make sure your main -ve bonding point (see other threads about why they're a good idea) is close to the engine.

 

Tim

[casper ghost]

Not sure what you mean about the main -ve point.

I've looked at another HR2 and that starter motor wasn't isolated either so think I should be ok getting the cheaper one.

We've purchased a propeller now, a 22 x 22.5, which works out fine with the on-line prop calculator and I found a chap with same engine layout and he had a 22 x 22, so should be ok, a good buy too at #81.00 including delivery. We're going to look at the throttle next week, it's a slow job marinising an engine.

[casper ghost]

Hello again, just a quick update.

 

We have fitted starter ring and motor and the variable throttle. If you want to see the engine running my mate has put it on youtube, simply search for lister hr2.

 

Thanks to everyone who responded.

[Liam]

Is this the one?

 

[casper ghost]

Is this the one?

 

 

 

 

 

Yes, that's the right link.

[suterman]

Heya peeps, I am caspers and caspers brothers friend. I am helping them with the engine + gearbox setup and will probably get involved when it comes to building the boat (should be started in about two weeks) I generally stand about and point out things that I see could help and suggest ideas when they come to me. I have had no experience with narrow boat engines of building but like to tinker with other stuff that gets oily and hot and burns fossil fuels (old volvos specifically), I also normally take a few pictures and videos along the way whenever I am messing if I remember my camera (hence the YouTube vid posted in this thread)

 

Here are a couple of pics of the flywheel mesh guard we made a few weeks back..

 

 

 

 

Today we were working out the fitting of the gearbox to the engine, the output side of the crankshaft has a keyway and the input shaft of the gearbox is a drive spline. the two are coupled together using two adaptor flanges, the engine side flange have a keyway and the gearbox side being a spilined type, the two flanges being bolted together with 4 cap screws through threaded holes in the flanges.

 

We were trying to work out how best to line up the two shafts (crank and input) so as to give the least stress on the input shaft bearings. We came up with the idea of mounting the gearbox on a thick vertical steel plate welded to horizontal feet (with some bracing to give added stiffness) the feet of the mount being fixed to the engine bearers using vertical studs that can be altered using nuts and locking nuts on the underside of the feet to unload vertical stress on the crank/input shaft with oversize holes in the feet allowing movement to undo any horizontal stress.

 

Anyone have a better idea..?

 

Pics paint a thousand words.

 

Edited April 3, 2009 by suterman

[casper ghost]

Hello Sureman.. this forums gone right down hill now...

I think my idea to mount the gearbox is better, but hard to expain here.

What we don't know is how accurate does the mounting need to be? It's not easy to tell if it's exactly in line, we tried to fit it today but spent all our time messing around and thinking alot, not too much working though. Still, greatful for the help as always suterman.

[suterman]

Thinking is good.

 

Like your dad was saying, pehaps the best way to find the most central position of the box is to keep spinning the crank by hand and "feel" for the best position.

 

I think the trick of it in our case is to make a mounting that can be adjusted in height and side to side, (threaded mounts and oversize holes)

[RLWP]

Hello Sureman.. this forums gone right down hill now...

I think my idea to mount the gearbox is better, but hard to expain here.

What we don't know is how accurate does the mounting need to be? It's not easy to tell if it's exactly in line, we tried to fit it today but spent all our time messing around and thinking alot, not too much working though. Still, greatful for the help as always suterman.

 

Pretty accurate. We have a gearbox mounted on a bell housing attached to the engine that wrecked its splines because somehow the alignment was out. New driveplate and replacement gearbox.

 

Richard

[suterman]

Gary, here's a screen print of a quick model of my ideas I made on sketchup....

 

 

[Timleech]

Gary, here's a screen print of a quick model of my ideas I made on sketchup....

 

 

 

For that sort of thing to be successful, it'll need to be fairly heavily engineered, perhaps more so than you might imagine, and if you make it adjustable that immediately introduces flexibility which you don't want unless the adjustment method is also suitably heavy & rigid.

My own preference would be for the box to be directly mounted to the flywheel housing but it does have to be properly mounted and centred. The stub shaft on the engine can be removed and shrtened/adapted as required, you'll want to incorporate some sort of sprung drive plate into the drive.

 

Tim

[casper ghost]

Thanks. Our alternative idea was to mount the gearbox remote from the engine and have a short shaft either end with a plumber block holding it then a prop-shaft off a 4x4 between the box and the engine. This would remove the need to allign accurately but would mean the purchase of more flanges.

[RLWP]

Thanks. Our alternative idea was to mount the gearbox remote from the engine and have a short shaft either end with a plumber block holding it then a prop-shaft off a 4x4 between the box and the engine. This would remove the need to allign accurately but would mean the purchase of more flanges.

 

I'm sceptical about this, but I'll ask anyway. How are you planning to couple to the propellor shaft? Another pair of UJs and a cardan shaft again? Will you be using flexible mounts anywhere? Are you planning a rigid coupling to the propellor shaft, if so you will have to adjust the position of the gearbox, then the position of the engine.

 

You will be better off getting a bellhousing to mount the gearbox to the engine.

 

Richard

[casper ghost]

I'm sceptical about this, but I'll ask anyway. How are you planning to couple to the propellor shaft? Another pair of UJs and a cardan shaft again? Will you be using flexible mounts anywhere? Are you planning a rigid coupling to the propellor shaft, if so you will have to adjust the position of the gearbox, then the position of the engine.

 

You will be better off getting a bellhousing to mount the gearbox to the engine.

 

Richard

 

Well, now we've found a company that make rubber flexible couplings for industrial machinery, we'll see them about making us one to put between the engine and the gearbox, they say it allows for half an inch out of alignment, far more than we will need. I'm told there very strong and long lasting. Then i'll put a 4x4 prop shaft between the gearbox and the prop. Apparently this company can make rubber doughnuts which fit direct to the flywheel and the gearbox drive plate fits onto it. We won't use flexible mounts, we'll attach gearbox to engine mounts, which are oak beams. I hope this method will remove any need to align accurately.

[casper ghost]

Hi again. As a further update, i've contacted PRM and asked their technical manager about remotely fitting the PRM gearbox to this engine. I was told that the bearings on the gearbox will cope fine with a 4x4 prop shaft between the engine and gearbox, that way we can mount the box rigid to the floor so no lining up worries.

 

I must say that PRM have been extremely helpful to me, thanks alot guys.

 

My brother's painted the engine, here's a few pics..