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The elusive 224/3.7 MerCruiser banger

Discussion in 'The Hokey Ass Message Board' started by tjm73, Apr 9, 2008.

  1. drtrcrV-8
    Joined: Jan 6, 2013
    Posts: 1,707

    drtrcrV-8
    Member

    beck: I only referred to the Speedway electric pump to post a reasonably well known example ; they have been available from the marine supply houses for a very long time, & now even Harbor freight has a 12v pump available. I only presented it as a viable alternative to either the original pump, or to other add-on pumps, although I do like the crank-snout pump in a recent post(except for the increased length it requires !!)
     
  2. As to the pump, I went to the water pump shelves in a parts store and opened every waterpump box that they had to compare the pumps to what I thought I needed. The Toyota pump impeller is crude compared to a Mercruiser pump impeller, and power may be lost there but it does not have to pump a lot of water so it worked. An electric pump would save power that can be used at the wheels and the Harbor Freight pump is inexpensive enough. If you don't drive slowly, a fan spinning without its belt can spin the waterpump enough to cool an engine not running hard. (I did it once) Belt driven pumps can fail too.
     
  3. 34Phil
    Joined: Sep 12, 2016
    Posts: 553

    34Phil
    Member

    Make a bracket that mounts to the 4 cover bolts and anti-rotation boss you and could belt drive it backwards with pulley in front. (straight impeller blades). I think there is a street rod market for a version of the old McGurk front drives (yeah, I'm that old) that took water pump off the front of the engine and drove it, FI pump and oil pump from the rear of their front cover. Can you imagine how happy the SBF guys would be to replace a 5" long pump with a 1-1/2" thick adapter? Even the Snow White is 3-3/4". Short SBC is 5-7/8".
     
  4. beck
    Joined: Sep 20, 2008
    Posts: 292

    beck
    Member

    34Phil, I ran one of the SBC Snow White water pump risers on a '34 Plymouth a couple decades ago. It worked great. The Johnson pump is probably pretty rugged since it is made for marine use. I see it was also used in sea water, so I'm thinking a bilge pump. It probably was designed for slower RPM than I will be running, but if it was belt driven like you suggested that would be adjusted. I see several versions of it available. The one you showed was crank mounted, so I am guessing it would bolt to a harmonic balancer? Someone handy could mount one of their other models to the timing cover and direct drive it from the cam. There would be a gap between the timing cover and the pump eliminating the water into motor issue.
    I am also trying to be weight and battery power conscious. Electric - I will be running on the battery with no charging system. Sometimes electric motors create issues with EFI computers in that situation. Weight - I am limited to total vehicle weight and I am probably too heavy already.
     
  5. beck
    Joined: Sep 20, 2008
    Posts: 292

    beck
    Member

    There is a seal at the oil pump pickup tube to oil pump. I have 2 gasket sets here and that seal is not in either of them. When I disassembled my motors they all had a glob of orange RTV in that seal area. The seal was there, but the previous rebuilder must not have been comfortable with it.

    During clean up I had installed regular viton O-rings. That was about 2 years ago. When I got those pumps out preparing to install them, I found that o-ring was pretty loose and I was concerned. The OEM seal there was square shouldered, not round. I took some measurements and referred to an o-ring chart. It appears they are 210 square o-rings. I ordered several from online. They seem to fit great and really tightened up that joint.

    My concern now is the material of construction of those square 210 o-rings. I bought Buna-N. The chart says they are good for oil, but that hasn’t comforted me. Does anyone know much about Buna-N?

    Like a lot of small online parts, the shipping was more expensive than 10 of the o-rings. If anyone is putting a motor together now (Feb 2018 for later reference) and needs one, shoot me a PM. I will put one in a regular envelope and mail it to you.
     
  6. 34Phil
    Joined: Sep 12, 2016
    Posts: 553

    34Phil
    Member

    No, it is for engine cooling. Even have a face mount. This Sherwood pump is for Chrysler 318 and 360. Use a Ford 6 cyl. damper with v belt groove and save another 3/4". It's been ten years since I had my '66 PU but I recall the 240 in it had a single groove and the 300 was a double groove. Don't remember if 240 damper was shorter. 170 is. Same deal for Chevy 6 damper on V8 and you don't have to drill balance holes like on Ford.
    http://marineenginedirect.com/sherw...MIooHLt6WU2QIVTQOGCh0-1wnzEAQYAiABEgJx7fD_BwE
    [​IMG]
     
    Last edited: Feb 10, 2018
  7. Bolting a plate to the back of a car water pump could (with the right pump):
    1. cover the big hole at the back of the pump,
    2. be a place an outlet spigot could be mounted for pump
    3. allow for remote mounting like an alternator
    4. and a larger pulley could be fitted to reduce power consumption by the pump.

    Its cost could be about 10% of an accessory pump.
     
  8. Rootsgroup
    Joined: Jan 26, 2008
    Posts: 58

    Rootsgroup
    Member
    from Indiana

  9. beck
    Joined: Sep 20, 2008
    Posts: 292

    beck
    Member

    Rootsgroup, Which pump is that? Is the inlet hose going to clear the balancer?
     
  10. Rootsgroup
    Joined: Jan 26, 2008
    Posts: 58

    Rootsgroup
    Member
    from Indiana

    I'm not running a balancer. I will have to redo the inlet to suit. The pump was maybe Toyota of some sort, just what ever I thought would work out.

    Sent from my XT1585 using The H.A.M.B. mobile app
     
  11. Water pumps can be twisted around to any angle that you need. My Toyota pump fitted when upside down so I ran it that way--it did not care and gave no trouble.
     
  12. GearheadsQCE
    Joined: Mar 23, 2011
    Posts: 3,375

    GearheadsQCE
    Alliance Vendor

    Will be interesting to see how it runs with no balancer. I always thought that a heavy balancer was an important part of a 4 banger build. Even more important with the big bore and stroke of the Mercruiser.
     
    Last edited: Feb 22, 2018
  13. beck
    Joined: Sep 20, 2008
    Posts: 292

    beck
    Member

    Your going to have to rethink the front seal. The stocker won't work since it seals onto the balancer hub. I expect the balancer keyway would be in the area where a new seal would sit. You could make an offset seal holder to place it in a different spot or install a sleeve on the crank.
    Like GearheadsQCE, I though a balancer was needed.. I'm also interested in how it works.
     
  14. drtrcrV-8
    Joined: Jan 6, 2013
    Posts: 1,707

    drtrcrV-8
    Member

    It was mentioned way back : SBF dampner without weights(internal balance) fits. If you don't want a pulley mount, machine the mass off an old SBF dampner to make a sleeve to go into the seal (this also covers the keyway)
     
  15. Do dampeners work best at a certain engine speed?
    If rotating engine mass enters in here then would our engines need a dampener tuned somewhat differently than for a V8 ?
    It would seem that a Mercruiser alternator is heavy enough to act as a front flywheel but how would it compare to a dampener?
    I ran a 170 with an automotive dampener and it worked well enough in my car that I did not feel irritating vibration but I used soft rubber engine mounts (Chevy V6) and usually ran around 2200 rpm. It has very useful timing marks.
     
  16. 34Phil
    Joined: Sep 12, 2016
    Posts: 553

    34Phil
    Member

    I looked for divorced water pump and found Gates 43230BH for $50 for '06-'11 Ford Escape 3.0. Just have to find a press on p. steering V belt pulley w/ same shaft dia. 1-1/4" outlets.
     
  17. CNC-Dude
    Joined: Nov 23, 2007
    Posts: 1,031

    CNC-Dude
    Member

    Inline engines create and operate at different harmonic frequencies than V8 engines do. And their respective dampers are designed specific for those frequencies, so swapping them between the different engines, even though they may fit might not provide the results you're expecting.
     
  18. It looks like a steel pulley so one might, replace the center out of a larger steel pulley with the smaller one's center.

    There are several other similar stand alone water pumps like the one mentioned (eg Gates #43505)

    And BMW has been using water electric pumps in at least some of their cars for the last decade. They are heavy at 5 to 10 lbs compared to the belt drive pumps weighing a pound. And they use a stand-alone in-line thermostat that looks a bit like a turnip.
    For an electric pump, the power still eventually comes from the engine and there is extra power loss in the alternator and pump's electric motor.
     
  19. Good headgaskets for our engines have become much harder to find.
    Randy Dupre said that every head gasket but Mercruiser's leaked coolant into the lifter gallery
    I am going to add aluminum, widening the block's most compromised sealing surface...the narrow wall between the water jacket and the upper lifter chamber. The only time aluminum can be brazed on here is before the block is surfaced.

    "Printoseal" type gaskets by Mercruiser and Victor Reinz seal ok here.
    Felpro automotive gaskets with the needed sealing bead are available.
     
  20. update:

    Mercruiser gaskets may be still be available....I passed it up at $97 (includes shipping)
    Victor Reinz gaskets are still available (I called the factory) cost less than Merc gaskets and have a good reputation.

    The car gaskets? I've been told to not use them by several different people who should know.

    If you have a closed deck, the headgasket sealing
    problems should be less.
     
  21. A possibly safer alternative to welding the deck closed is brazing or soldering. Much less heat is involved and warping will be less. The joints strength would be proportional to the size of the joint.
    here are some possible materials for joining aluminum to the block :

    temperature name composition
    430 F tin silver solder (tin 96.5% silver 3.5%)
    430 F. Aladdin 450 (tin 96.5% silver 3.5%)
    392-480 F Al solder (tin 85% zinc 15% )
    509 F. Messer Mg 460 (composition not specified) )liquid flux
    585 F Aladdin #33 (tin 60% zinc 40%)
    710 F Alux core 98/2 (zinc 98% aluminum 2%) flux core rod
    720 F Alumibraze (not specified) fluxless
    742 F Aladdin 3 in one (not specified) fluxless
    800 F Alux core 78/22 (aluminum 78% zinc 2%) flux core rod
    1070 F Alux core 4047 (aluminum 88% silicon 2%) flux core rod

    Aluminum has a sharp melting point so it suddenly melts causing control problems.
    one* of the solders above melts over an 88 degree range. This behavior is fairly common.
    As aluminum melts at 1221 F , it would seem safer to use a solder that melts at 800 or below.
    Tin by itself melts at 450 F and it is soft. Zinc is said to be brittle and if not alloyed melts at 787F.
    The hottest I ever saw my engine was 262 F so you can see the possibilities.

    There was very great difference in those I used.

    ps: they could be called either solders or brazes but no welding is involved no matter what they claim.
     
  22. I Found our head gaskets:
    You want a Mahle headgasket the part number is 3909VM
    It is available from:
    Amazon $56 one available at present....... free shipping
    -----------------------------------------------------------------------------
    Summit $66 ........................ $56 + $10 shipping unless your order exceeds $100 for free shipping
    -----------------------------------------------------------------------------
    Advance Auto parts ( Carquest) $77...... $62 + $15 shipping
    ------------------------------------------------------------------------------
    a boat parts place..$97 includes shipping but at that price I don't care what their name is
    ______________________________
    detail on why this head gasket thing is so complicated:
    Victor Reinz made the original Mercruiser gaskets, the only ones that did not leak coolant according to Randy.
    Victor Reinz was bought by Dana. Bankruptcy was declared.
    Mahle absorbed Victor Reinz. He said Mahle gaskets are (depending on the gasket) made in a Dana factory. The name Victor Reinz is used in Europe the name Mahle is used in the USA.
    Mahle "makes" the factory original gaskets, the ones you want. Excellent custom gaskets are made by Cometic, a sister company of Mahle also owned by Dana.
    Advance is also in this as a corporate owner.

    It seems as though the "suits" had a field day with this.

    Clevite, Felpro and Federal Mogul are completely on the outside of this. Randy wrote that because of Mercruiser 3.7 liter block design sealing difficulties, "only Mercruiser gaskets don't leak" in a Mercruiser 3.7 liter block (although others will fit). That was posted years ago near the beginning of this thread and gasket design can change in a decade so perhaps they work now but as there is so much at stake, I'm ordering Mahle 3909VM from Summit. Summit said the gasket would be about a month out, but it came in less than a week. Looks like an ordinary head gasket???

    I feel like I'm "talking to myself" so I'm going to shut up for a while. Hope this info helps you
     
    Last edited: Apr 29, 2018
  23. GearheadsQCE
    Joined: Mar 23, 2011
    Posts: 3,375

    GearheadsQCE
    Alliance Vendor

    Dennis,
    I'm listening. :)
     
  24. studebakerjoe
    Joined: Jul 7, 2015
    Posts: 1,136

    studebakerjoe
    Member

    Dennis, thanks for the head gasket info.
     
  25. Rootsgroup
    Joined: Jan 26, 2008
    Posts: 58

    Rootsgroup
    Member
    from Indiana

    Yes, I know I I'm not getting much done, working on the car right along with the engine, as much as I can. Little update here. IMG_20180612_101726_818.jpeg IMG_20180612_163234316.jpeg

    Sent from my XT1650 using The H.A.M.B. mobile app
     
  26. Rootsgroup
    Joined: Jan 26, 2008
    Posts: 58

    Rootsgroup
    Member
    from Indiana

    If its a help, I just ordered the Sierra head gasket set from Wholesale Marine. $74.13 shipping and all. They did show out of stock on just the head gasket itself.
     
  27. Unique122s
    Joined: Jun 19, 2018
    Posts: 8

    Unique122s
    Member

  28. Unique122s
    Joined: Jun 19, 2018
    Posts: 8

    Unique122s
    Member

    Good evening everyone. Wow, what a fascinating thread. It took me several days to read all of it. I have a lot of pasted notes. I'm looking at diving into this adventure too. I picked up a 170 with only 200 hundred hours on the meter. However, the motor is locked. but it did have good looking oil and antifreeze in the closed loop system, Unfortunately, the boat had to come with the motor. The project that I'm going for is a street cruiser in a 1965 Volvo 122. I think this should be an awesome build. I can't wait to tear into the motor and see what I have to work with. My plans are to keep it fairly stock innards except for self contained EFI, and or course address the water pump, alternator issues and add an aluminum aftermarket head. I'm thinking I'm wanting an automatic since this is going to be a street cruiser but that is not set in stone yet. Any thoughts? I has so excited when I got the engine home I had to just set it in to be able to compare the size. Again, WOW, width is not going to problem, one reason that this build appealed to me but I was not prepared for how long this big bore 4 banger is!

    Sorry not sure why my pictures posted without the above message.
     
  29. CNC-Dude
    Joined: Nov 23, 2007
    Posts: 1,031

    CNC-Dude
    Member

    Just scored an almost complete 3.7L engine and an extra block, crank and head with misc. other goodies. I've had several on here express interest in wanting some custom performance and racing parts for these engines, so i'll get busy!
     
  30. BuiltFerComfort
    Joined: Jan 24, 2007
    Posts: 1,619

    BuiltFerComfort
    Member

    From your name, I have a question - are you going to make a deck plate for your motor? That seems to be a performance limitation for these.
     

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