The elusive 224/3.7 MerCruiser banger

Why not just use an electric pump ??

 

So ive been reading this entire thread over the last few weeks.... amazing work, simply amazing.

The question is has anyone come up with an external water pump "kit" like there is external alternator kit.

These engines in stock to slightly modified form with fixing the Water pump and Alternator problems would be a great simple engine.

Again really nice work.

 

res0wc18,

You are right about the simplicity of these engines and they are notable for their broad torque curve.

Some have said that they require a lot of RPM to develop their Hp and while that is somewhat true of the smaller 3.0 Chevy 4 Mercruiser is isn't true of the 3.7 Liter 470.

Mercury Marine sold the 165 hp 6 cylinder that was a 250 cu/in Chevrolet engine during the same time that they sold the 170 to 190 hp 470 series engines and they did not have the wide range of torque that the 470 had.

They had the torque in the low range but did not have it at 4800 rpm where the 470 produced 190 HP.

That is not to say that a 250 cu/in 6 can't produce that and more in a car, but in a boat they have to produce that all day long at full throttle up against the maximum resistance of water.

The 470 Mercruiser was able to do that for many hundred hours with proper maintenance.

I have several engines that still have standard bore, no taper and pistons and bores that still show machine and hone marks.

You seldom find that in other engines that are in boats that are otherwise junk.

My marine engine mechanic friend says that there are stand alone water pumps available. I will quiz him to find out who makes them and how much they cost.

If they are too expensive I will use the Toyota water pumps that I have.

They just require a flat aluminum back cover plate with a water inlet to make a stand alone pater pump.

I will make the back cover plate with flanges that I can drill mounting holes in to provide a place to connect the appropriate brackets.

These water pumps will provide plenty of cooling for the aluminum blocked 470.

Dick

 

Check Mercruiser fuel pump number for 470 and check one for Mercruiser SBC and SBF and you should get your answer.

 

Ray-jay // I used electric pumps before but when i saw "Race pumps" new design (progressive) I wanted to trie it (and no cabels at all).Not really new. We used them in hydraulic systems a for long time. The god thing is that you can have a small pump when you use 100hp and you can have a big pump when use 1000hp. Anyhow I wanted to try one on my injected turbo mercruiser.
.
Phil 1934 // I should look into that.

Johan

 

Awesome. So the question is if one were to donate to one of you guys's restoration fund, whatever you think is fair would you be willing to make more of the aluminum plates etc needed to convert to the external type water pump?

From what i can tell two people have done this?


Here is some ideas for electric water pumps

http://www.summitracing.com/parts/EMP-E558ABK/
http://www.summitracing.com/parts/CVS-8000CL/


Belt Driven
http://www.asap-supplies.com/marine...ng-pumps/pump-kit-jabsco-3-4-bsp-127mmpulley?

http://www.jabscoshop.com/marine/pu...h-127mm-pulley-replaces-6490-252-6490-222.htm



http://www.mackengineering.co.uk/product_downloads/52040-2001 dimensions.pdf

 

Does anyone know what diameter the stock balancer/pulley is on these off the top of there head?

 

7.7" on mine

 

thank you kind sir.

According to my calculations that means with the main pulley/balancer pulley spinning at 800rpm(idle?) the Jabsco pump would be pumping 7.8 gallons a minute (10.56 gallons a min at 1500rpm)

Using this same idea running at 2800 rpm it would be pumping 20 gallons a minute. For a raw water pump this is more than adequate from what im told on a 350 Chevy. So i would assume that this would be even easier to cool.

I'm not sure what the stock water pumps move originally in the marine setup, but considering that a standard water hose flows from 10-20 gallons a minute, and that is what most use to flush there engines etc etc this sounds sufficient.

Does anyone have any pump performance information on those Toyota water pumps?

 

As for the stats, you are welcome, but I need to correct myself. I was writing from work, and from memory, and didn't know where you were heading with using the figure. I remeasured and the OE "balancer" (it's just a hub, not a dampener) is more like 8.2. But the pulley is only about 5.8 OD. Not much over 5.5 once the belt is down in the groove (not sure how they are measured).
Now, as for flow... I know I have an Edelbrock catalog that shows them developing their line of race pumps on a "water pump dyno", and the figures are that on a small block Ford (ie 302 or 351w) each side of the pump produces 32 gal/min at 4K rpm and 40 @ 5k rpm. So, 64-80gal/in for a 450-550 hp motor. I do know that CSR and companies like that, do make the electric pumps for drag cars, and they advertise 35 & 55 gallon models. My own experience as a counterperson at a performance parts retailer, is that those who try to run them on the street experience overheating even in mildly warm temperatures (80-90F), and, incidently that those aftermarket electric water pumps are not durable, even the expensive ones.

So I would say that our Mercruisers making 190-300 hp, may need anywhere between 28-50 gal per minute ideally, to be 100% safe. A Toyota, puting out betwen 70 and 135 hp, on the common older models may not have the capacity. Thinking about the 28-50 figure- Probably on the low end of that, honestly, being all aluminum (at least most of ours are...). and with free flowing exhausts, light cars, and as big a radiataor as we can want (b/c if it does't do the trick, a bigger one can be put in.) It's not like we plan to do towing....
But, I know with an Off-Topic car type, some friends where kind of shocked that a long hill in the mountains caused their turbo cast iron exhaust manifolds to glow red in daylight. Kind of makes me think that aiming for the least heat a motor could generate and ignoring what you might do, someday, is a wrong move. Yeah a huge capacity rad can be a heat soak for some Banzai runs, but its just plain better/smarter to set it up so it can rid itself of the heat on an ongoing basis.

Up until last week I would have said put the speedi sleeves on, put new seals in and let'r buck, not to mess with OE engineering.

I am re-examining this cooling flow thing, because I am looking at my specific project using a Kaase Boss head, I think I want to try something used on the Volvo engines of the 60's though 80s'. No direct coolant flow in the block. Pump the flow into the rear of the head and let it flow out into the rad once it's hot. I'm also thinking of a warm up circuit using a 5 pin HEI module that when the one pin is grounded, it takes 10 deg time out for faster warm up. The Canadian in me coming out...lol

 

yes, i sent an email to CSR about there duty rating etc etc and still have not heard back, its been over a week. That would lead me to believe electric is out.

I think using the toyota water pumps or something similar is really the only solution for reliability sakes etc etc.

If someone were to give me a 2d flat pattern CAD file for the aluminum plates such as the two guys on here have done, i could torch them out on my buddies plasma table and we could work back and forth till we had something that was a bolt on to frills solution.

 

Btw, the one "rational" (spelling?) magazine push for electric water pumps (and fans) is the HP savings. That's BS... they have light duty chassis dyno's or fast rise engine dynos that measure flywheel effect- and a factory fan has a lot of flywheel effect. So take the fan off and the engine revs faster. That's not usually as benficial in the real world as the numbers they give would indicate. Absolutely benefit-less in top speed and in towing on a hill, for example. The actually steady state HP to drive a pump is small- plus you eventually put the electrical power back in. So you have a water pump using 10 amps and a fan using 45+, how much does it take to turn the alternator?? The OE''s use them so you can shut down the drag during steady cruise, like an EPA mileage cycle. Hmmm.

Here's a pump I'd consider:

http://www.summitracing.com/parts/EMP-E389A-BK34/?rtype=10

What about the LT1 pump? I like OE stuff... Edit/// nah, might not be possible to handmake a housing to mate with it that has really good flow, just by eyeballing it... I thin some serious understanding of flow goes into those

 

actually I think aside from the Jacobsen one shown above, the building of the housing is going to be the downfall of this idea...

If you aren't put of yet, here, forget Toyota pumps:
http://www.stewartcomponents.net/Merchant2/merchant.mvc?Screen=CTGY&Category_Code=BMWHPWP

Start with that...

 

When you look at a typical thermostat and see how restrictive it is even when open you will realize that a great flow isn't necessary.

The faster that water flows thru the radiator the less heat is transfered to the air going through the radiator.

More radiator surface area and more air through the radiator are much more important than high water pump flow.

Also remember that if an aluminum head is used on the 470s aluminum block with the open water jacket these engines should be easy to keep cool.

The original Mercruiser water pump ran off the front of the cam shaft at 1/2 crankshaft speed and flowed through a small opening into the front of the block.

The Toyota pump will run at faster than crankshaft speed and it has a more positive type of impeller than the Mercruiser impeller.

I would not pay the high price for the Jacobsen pump.

I just bought a 1979 Toyota Corola water pump for $14.00 delovered.

Ebay:: Water Pump Cardone 57-1005 Reman Disaster Recovery Make Offer No Core Charge

I bought a piece of 1/4" X 5" X 5' aluminum for $25 thats enough to make 12 back plates for this water pump making the aluminum about $2.10 for each plus what ever the cost of the water nipple that I will install on the back of the waterpump plate.

The only other thing in making these is to cut the plate to fit the back of the pump and tap the hole for the pipe nipple.

A nipple could be welded to the steel plate that comes on the back of the water pump but I like the aluminum plate better.

See the picture below.


Dick

 

I ran my engine on a test stand 30 minutes at 4000 rpm cooling it with a garden hose. As it is on a [water] well, that puts out 10 gallons per minute. there were restrictions in the hose so it as not even that. It did not overheat.

I use volvo radiators...cheap ones and did have to go to a thicker core. [temp then dropped 70 degrees F].

 

Dick, I was concerned about pump impeller cavitation, but it seemed not to happen. it runs roughly 2x crank speed

 

Dick, just put the toyota pump on top of the mercruiser pump rear half.

The spacing works so the pulleys even line up. no need at all of any other connections, with no more than an adapting plate, my toyota pump blows water directly back into the old merc pump cavity and thence into the engine.
I fitted little welch plugs into the extra openings in the toyota pump.

As to reliability, the belt must stay tight or it can come off. for that reason I think the $240 electric pump is a good option. especially for a high output run of a few minutes or less as there will be less power loss and there are no belt reliability issues. I had an engine throw a belt and cook itself. an attached fan would function as a reserve drive for the water pump, but not electric fans.

But I am not running an electric pump as the toyota pump does a good job and is cheap.

 

Absolutely right. more rated pump flow just takes more power. Mine cools well.

ps: I'm running mine with no thermostat and it now stays at 180 winter or summer.
I don't know why it does that but that is what I saw .
If it runs cooler I'll just cover part of the radiator. Simple things fail less.

 

It looks as if you have to make a housing for it unless it goes into a bmw housing. It is a nice pump but there are equally nice pumps with that impeller which cost much less . I'll stick with toyota

 

Dennis,

The reason that I run the bracketed pump is that I am going to run an electric fan on the top half of the radiator.

Taking the water pump inlet and cover off makes more room so that the engine can be as far forward as possible and not interfere with the electric fan shroud.

I will mount the water pump close to the intake side of the engine which allows the hose to the inlet to be very short.

I will mount the alternater or generator on the opposite side to adjust the tension of a single belt.

Both of these will be lower than the fan shroud.

I hope to make the fan shroud deep enough to somewhat hide the electric fan.

I like your setup and when I build a car with more engine room I will use your approach as it allows for a fan to be attached in the appropriate position.

I am going to fabricate some of the Toyota water pumps for future use.

Dick

 

lets keep information going on this, maybe if were lucky someone will come up with some dimensions or a basic set of drawings etc so i can then recreate into CAD files


The biggest issue im gonna have is even if you send me the template etc etc i would have to check fit back and forth on an engine block etc etc,,,,, all this is possible but time consuming. So thats why i say if someone came up with some drawings or something it would speed things up as my boat engine is not torn apart and im in the middle of moving into my new place.

I would be more than happy to get these worked into a kit form or whatever, but again we need something to start from.

Most all of my trucks and deuce and halfs i have created many many parts from cad files, but i had the product in front of me to measure, make , check fit remeasure remake etc etc etc.

I think there is a big calling for something like this though as i know many people that still have these motors and never having to worry about water in oil again would be priceless to most of them.

 

Dick
I have a foot or more room for things ahead of the engine, so it was easy for me.
I changed axles to get more room.
It may be easier to move the radiator forward and have a longer hood than to use a remote belt driven pump.

and the fan will not show with the hood shut.

 

Dennis,

The first install is going in a stealth mode stock Model A Ford.

I am trying to avoid as much modification to the firewall as possable.

I am using a 4 bar suspension with a Vega steering box and a cross steer setup.

I will put the oil pan as close as possible to the steering member.

One of the reasons that I took the original alternator harmonic balancer off was to gain a little room behind the front crossmsmber so that I could change the belt without having to jack the engine up.

As you know it's the little things that can bite you if you don't plain ahead.

After the first sucessful install the others will be easy. I plan to use the cookie cutter approach making improvements as I learn better ways to build them.

I think that I have found a good basis for light weight sleepers built around the 3.7 Mercruiser.

I start with good looking, light weight, pre-smog, 4 cylinder cars that have the room for this Big Block engine.

So far the plans include Model A Fords, the Volvo 544 and I may even slide one into a 240Z the only 6 cylinder car I am presently looking at.

I would call it a 370 ZX Turbo. with 300 hp and great torque it would be a fun machine. I believe that I could maintain the 2360 lb. weight while doubling it"s hp.

I am having fun just thinking about it.

Dick

 

Parker, I'm not ignoring your request, for a pattern. I will make one the next time I have that part of my motor apart, but it could be several years until then.
As you can tell, I don't want to take my car and only motor apart for something that I have no need for.
-----------------------------------------------------------------------------------------
Making a pattern is a simple process that anyone can do successfully:

1. lay a sheet of white paper on the timing chain cover/ rear half of the water pump

2. clamp or hold it in place over the casting

3. rub a finger over the paper to make a pattern of the sharp edges of the part. now you have half of your pattern. trace it with a pencil to preserve the marks

4. now place the pump on the OPPOSITE side of the paper oeriented so the spout and its associated hose does not interfere with any critical parts.
You have freedom to move it around as needed.

5 rub a finger over the sharp edges of the pump casting and you have the completed pattern.

6 tape it onto some aluminum, cut it to match the outermost set of lines and drill the mounting holes and the water outlet hole

7 try mounting the plate and file into position any holes which were drilled slightly out of position.

That is all there is to it. Takes no more than ten minutes.

 

Dick, what is cross steer?
I went with a toyota non-power rack and it is a huge improvement over the old box I had been using. [ more positive, no longer vague and just the right steering rate].

 

Res, I will try to get a cad file for you, I have one apart right now, I have a couple of 190s sitting in my shop, one for parts...I am building a small jet boat [ 80 % done] and this is my power choice because of the power to weight ratio..and i have them.
Thanks to all for the excellent info in this thread !!!!!!

Curtis

 

i know, and i could easily make a pattern to manually cut it out once i get moved in etc, but thats not my intention. My intention is to get these dead on accurate on autocad so i can cut them out and supply any and all of those who want/need them in a form where they could just cut their cam, plug the hole on cover and bolt these on with the yota pump and never worry about water in you're oil again


Curtis that would be great.

 

Hi guys - I've been lurking on this thread since it started & just wanted to thank you all. This is what makes hot-rodding fun, the shared discovery, help, and friendly banter. I don't have this motor (though I'd now consider one) but I love watching where this is going. Keep up the good work and good posts.

Tom

 

Dennis here is a picture of cross steering. Borrowed from Speedway.

This configuration is pretty good if it is set up right there is not much bump steer.

I made mine so that in the straight ahead position the drag link is parallel to the tie rod.

Making it more parallel than the Speedway diagram not only makes it look better but it also allows the 470s full pan to be clooser to the front of the car while extending below the drag link.

The steering box is quite far forward on my chassis. This is not a problem with the 470 because it has more room between the engine and the frame and the motor mounts and exhaust manifold are not going to be in the way.

This steering box is actually a Saginaw bos off a full size chevrolet. I am trying it because I had it in my junk and it is has a quicker ratio than the Vega boxes that I have.

I also made the Panard bar run as close to parallel and level to the axle as possible.

Because of the lingth of the drag link and the fact that the suspension only moves up and down a few inches the arc at the end of the drag link during suspension movement is minimal.

That all adds up to very little bump steer.

Some cars built by those who do not understand the geometry of the straight axle suspension system have a tendancy to steer badly while hitting large bumps in the road especially pot holes.

The steering wheel will almost pull out of your hands when the car is hitting bumps.

Dennis, What model and year water pump did you use and what pulley did you use to get it to line up with the crank pulley ?

And what harmonic balancer and pulley are you using on the crank ?

Dick

 

I fabed up the same type of steering on my rock crawler except the box is in front of the axle, works good.
I plan on eventually putting one of these motors in the crawler as well.

Curtis