Force 50 water flow

[ozarkjeep]

I read with great interest the message below abouth the force 40 HP water trickle.<br /><br />well mine doesnt do that, nothing but exhaust smoke comes from the 2 hole in the mid unit.<br /><br />Ive removed the lower unit, checked the impeller ( it shows some wear but I think it would have moved SOME water)<br />and I tried blowing compressed ait rhu the passages.<br /><br />from teh plug in the top of the cylinder head to the copper/brass tube that plugs into the impellor housing , thats a straight shot no detectable flow restriction.<br /><br />BUT when blowing from teh bottom and pluging the top with my finger it doesnt come out at the 2 mid placed holes.<br /><br />so I removed the thermostat to see if thats where the blockage is, no dice, even from teh lower port in the thermo resivior I cant get any appreciable amount of flow to the mid holes OR the lower unit exahust/water cavity.<br /><br />is this normal?<br /><br />Im thinking htere is something lodged inside, but Im guessing, and really grasping.<br /><br />the previous owner told me it would only run with the cowling off, which I never understood until I realized it had a cooling problem, so its problably been overheated alot or severaly.<br /><br />what should I check or worry about at this point?<br /><br />it starts on the first revolution, and seems to idle smooth ( although I havent let it run for more than about 20 seconds)<br /><br />any help is greatly appreciated!<br /><br />oh yeah Im headed to the library tomorow to pick up a clymers manual.

 

[hondon]

Re: Force 50 water flow

Well force 50 not only do you have a cooling problem but it also sounds like you have a health exhaust leak. The two are hopefully related i.e. power head gasket.

 

[12Footer]

Re: Force 50 water flow

Did you see any water on the plugs? Probably not, but do check them.<br />I suspect a corrosion blockage under the exaust port plate .<br />You'll need a compression gauge and a port plate gasket. It sounds bad,but it's as easy to check as replacing a blown lawnmower head gasket.<br />Watch your torque wrench carefully, as it's<br />alluminum/alluminum,and the threads may be in rough shape to begin with. I would chase the block threads with plenty of liquid wrench spray and a head bolt before resetting the plate.<br />Also,check all ports to and from the plate chamber with a straightened coathanger (carefully of course).<br />You can do it with the shop manual and proper tools. Good luck.

 

[12Footer]

Re: Force 50 water flow

OOops..Forgot something...Hondon is right on also,as it could be a corrosion blockage under the head too,which I would check first (because it's even easier to get at).<br />But first, you mentioned signs of wear on the impeller. Did you replace it? The impeller should have round beads at the end of the vanes. If these have worn off, the vanes wont contact the housing enough to generate any water pressure,esspecially at idle speeds.

 

[ozarkjeep]

Re: Force 50 water flow

I havent yet replaced the impeller ( yet, although I have another one), but it did have the round beads on the end, it was tight inside the impeller chamber.<br /><br />I did try last night a coat hanger thru the top plug and it went in a little but not enough.<br /><br />so where is the other port? is it on the opposite side of the head?<br /><br />No water on the plugs<br /><br />IM confused as to how this condition indicates an exhaust leak?<br /><br />Im heading to the library so that maybe a coolant circulation chart will clear this up for me !<br /><br />thanks for the help guys

 

[12Footer]

Re: Force 50 water flow

The exaust port plate is on the port side of the engine,under the terminal blocks...Yeabuddy, the head is much easier to pull.<br />Not exactly an exaust leak, but water can be forced-into the combustion chamber by water pressure outside of specs. I would not be too concerned with this, esspecially if you have no signs of water on the plugs.<br />It's not the head or exaust port plate gaskets that have failed here, it's the openings in the underlying water jacket.<br />Before digging to deep,pull the T-stat and run the engine ,just long enough to eliminate the T-stat as suspect. They stick closed,and must be replaced allmost every season. Run it 20 minutes or so without the Tstat, and it MAY even allow enough flow though the jacket to blow-out any blockages.<br />But I wouldn't count on it, as you had it out once. Did You note any improvement then?<br />If you get steam out of the exaust port holes, you have good cooling. Most of the cooling water exhaust exits from the under the cavitation plate anyway.

 

[12Footer]

Re: Force 50 water flow

I hate to keep replying, but forgot something else. With this engine, test it in the water,or in a tank. The intakes on these engines don't allways take to muffs (my 50HP for instance).

 

[ozarkjeep]

Re: Force 50 water flow

no I actually havent ran it since I removed the Tstat.<br /><br /><br />let me ask you this, maybe my method of verifying flow is bad? Im trying to blow compressed air thru the bottom hole in teh thermostat recess, where should it exit?<br /><br />the tstat seems to move freely, I can squeeze it by hand.<br /><br />thanks for your patience! the librabry isnt open for another hour!

 

[ozarkjeep]

Re: Force 50 water flow

hmmm, so the muffs might not be suffeceitn huh?<br /><br />I wonder if I can fit it in a 5 gal bucket, since I dont have a lake or a tank handy.

 

[page62]

Re: Force 50 water flow

You can buy special Force muffs. Probably around 15 bucks. <br /><br />I use a set on my Force 50. (They work on my Volvo outdrive, too.) They're kinda squared off, like somebody cut two edges of a set of round muffs.

 

[JB]

Re: Force 50 water flow

Hey, Ozarkjeep. Is this the same Force 50 that you are getting 45lb and 65lb compression? If so, I take back what I said about carbon. You probably have galled bores, broken rings, warped head and/or all of the above. Just decide whether to overhaul it or replace it. I recommend the latter, and don't get another used Force from a crook.<br /><br />JB

 

[ozarkjeep]

Re: Force 50 water flow

same one jb<br /><br />so is there no way the head gasket or something else can be to blame?<br /><br />It owuldnt bother me to run it with low compression ( as long as it would MOVE the boat)<br /><br />I have since noticed that the water pump cant build a prime with my earmuffs or my shallow 5 gal bucket, so Ill have to find a larger tank, or a lake and see if its got any water flow at all.<br /><br />I got it cheap enouhg I wouldnt call the guy a crook, i had figured on a merc replacement.<br /><br />thanks for the help

 

[hondon]

Re: Force 50 water flow

Texhaust leak theory is supported by the fact that the previous owner told you this thing would only run with the cowling off. That means you are leaking fumes in the P.H. area. Now that comp.reading is not enough to support adequate combution and yes could be caused by head gasket. Pull cyl. head and let us know what you see.

 

[ozarkjeep]

Re: Force 50 water flow

sealing ring on top cylinder has a 1/8 opening burned away<br /><br />several opens in the water passeges also.<br /><br />cylinder bores look OK, , nothing major<br /><br />some small lines in the top cyl, showin ght eback and forth motion of pistion barely discernable with a fingernail.<br /><br />now what?<br /><br />where dfo I get a head gasket and how much?<br /><br />and how do I fix this clogged colling system?<br /><br />thanks

 

[12Footer]

Re: Force 50 water flow

Try this site link for gaskets. I've never ordered anything here,as I get all my parts in town from the Mr Quicksilver himself, at Outboards Only..<br />But here is the link. http://www.outboardparts.com/pindex.html <br />From your description, you caught it in plenty of time. This is what seperates the happy boaters from the sad ones...Both eyes on preventive maintainance

<br />I would not even worry about water flow until this compression leak is found and fixed.

 

[ozarkjeep]

Re: Force 50 water flow

ok, head was cut flat, I bought new head gasket, and I bought a big garbage can to run the engine with the impeller housing submerged.<br /><br />here is what it does.<br /><br />starts and cranks very easily, idles smooth. sprays mist of water exhaust from the 2 holes about 2 feet out.<br /><br />ran without thermostat for 15 minutes, then replaced thermostat and retorqued head gasket to 270 in/lbs<br /><br />the problem is it slows down and eventually dies with the cowling installed, I looked underneath the cylinder head and it seems to be exhaust smoke and dribbling water from under there somewhere, the exhaust port plate gasket SEEMS to be dry, just beneath the head, or possibly the seal between poherhead and lowe unit?<br /><br />is there a seal between powerhead and lower unit?<br /><br />there is no water on the plugs BTW.<br /><br />thanks for the ongoing help

 

[12Footer]

Re: Force 50 water flow

There should be a series of small (about 1/4") holes on the bottom of the case housing.These should be open. They plug with debris sometimes, and the engine cant get enough air. However, there is a problem there. Water should not be comming from the powerhead. Check the tstat gasket first (cheapest and easiest). The 120HP has a problem with the gasket under the exausr port plate, but on the 50HP,I've never seen one fail (not that they don't...I just haven't seen it).<br />Check the reburn return hose from the fuel pump. It may be disconnected or leaking.<br />The propshaft/water pump housing seal and the discharge tube are the only seals between the powerhead and L/U on the water curcuit. It's unlikely that these would pump enough water up to the powerhead,even under extreme conditions. It would overheat first. The two exaust ports double as the telltale on this engine, so the spray is normal.<br />Also, consider pressure-testing the lower unit,espaecially if the if the gear lube has gone grey or streaky.

 

[12Footer]

Re: Force 50 water flow

ooops. I said "propshaft" seal, and meant DRIVEshaft/pump housing seal.

 

[ozarkjeep]

Re: Force 50 water flow

well, it isnt coming from teh tstat housing gasket, it appears that a very slight amount is coming from the exhaust port plate, bottom corner.<br /><br />but the majority seems to be coming from the sealing surface at the very base of the power head.<br /><br />its hard to see down that low with the lower cowling on, ive been looking for my littel mechanics mirror to try and get a better view<br /><br />thanks for the advice

 

[hondon]

Re: Force 50 water flow

O.K. Now that we have the head gasket thing fixed lets do another compression test to make sure we are not kicking a dead horse. Those up and down lines are not good news.