What to do

[ghtiekjr]

I purchased a 1991 Bayliner with a 120 HP Force L drive. Engine Model 120-LD91E Engine Serial # 1393. Three of the four cylinders have a psi of 150, the forth around 50 psi. I am sure I'm looking at a over haul. One of my questions is:<br />1. Should I over haul the force engine or replace it with another brand of motor? (I have heard Force is somewhat a problem brand)<br />2. Are there other brands of engines that are enter changable mounting wise to the lower drive unit and motor mounts?<br />3. What would be a fare price to rebuild the force engine?<br />I am somewhat mechanical minded but have never rebuilt a boat motor. Could I do this with a good repair manual or is this more speciallized than I think<br />Thanks in advance

 

[The Marine Doctor]

Re: What to do

Before you really need these questions answered. Remove the head and have a look inside. You might just have a blown head gasket.<br /><br />TMD

 

[ghtiekjr]

Re: What to do

I had a mechanic biefly look at this motor. He told me I would be getting water back through the carbs if I had a bad head gasket. Is this true? <br />Thanks

 

[The Marine Doctor]

Re: What to do

Nope...the water can not get past the reeds.<br /><br />Your engine does not have valves.<br /><br />TMD

 

[ghtiekjr]

Re: What to do

OK, Took head off and piston # 4 has three dents or chips around the top edge. Clynder scored where these chips are. Head gasket seemed fine but there was gas on one head bolt and on head gasket.The gas could have come from the cylinder The Head on cylinders 1 & 2 have some carbon build up which I feel is normal but 3 & 4 Are clean as a whistle. Seems odd to me. Where should I go from here? THanks

 

[OBJ]

Re: What to do

If they are kinda shiny, would suspect water getting in there or running on the lean side.

 

[jasperpso]

Re: What to do

i wouldn't call force problem brand. They just dont have oil injection like newer motors.. but are otherwise reliable as the rest.. I do feel that there horsepower rating is a bit overstated.. i have heard it is cause they measure hp diferently.. but not sure.. some have a sorta problematic carbs, but i for one havent had much trouble with my force 50 at all.. If this motor pushes your boat at a adequate speed, and you are otherwise happy with it, you cant go wrong fixing it.. if for nothing else as a trade in if you do want a new outboard. <br /><br />just my 2 pennies worth<br />jasper

 

[The Marine Doctor]

Re: What to do

If there is scoring and dents it is rebuild time.<br /><br />Also before you rebuild..get the block checked for cracks.<br /><br />TMD

 

[alcan]

Re: What to do

From your description, it sounds to me like the head gasket may have leaked water into the cylinders causing the damage. This might account for the steam cleaned look of the two holes. As what do do at this point? Good question. This is something you will have to decide for yourself. If you are a fairly good mechanical hand and you want a project and a motor to use when your done and you do not really care about resale value, then this motor might be great fun. Keep in mind that you may have trouble trying to get a return on your investment on a resale. If your goal is strictly boating, fishing,etc. You better sell this rascal for parts and buy another motor. Again if your not an outboard person, I suggest paying a little more and buying from a reputable dealer, especialy if buying used. Just my opinion.

 

[ghtiekjr]

Re: What to do

Thanks for all input I guess Im back to some of my original questions<br />1. Are there other brands of engines that are enter changable mounting wise to the lower drive unit and motor mounts?<br />2.What are they?<br />3.Approx How much am I looking at cost wise?<br />4. What would be a fare price to rebuild the force engine?<br />I am somewhat mechanical minded but have never rebuilt a boat motor. Could I do this with a good repair manual or is this more speciallized than I think<br />Thanks in advance

 

[jokey1]

Re: What to do

Hey I just rebuilt a 1990 L-Drive. It is not so hard. I ordered a set of wiesco pistons with the wrist pin bearings and gasket set. Cost was about 500 bucks. I dont know why mine died but all I know was that every ring on every piston was broke on the exhaust side causing deep grooves. The hardest thing about putting the engine together is setting the pistions in the block and putting the connecting rod together with out loosing the needles. After that it is a snap.<br /><br />I have put about 180hours on the boat since the rebuild and all of them were pulling people. In thoes hours I have serveral problems. At about 50 hours I had to replace the sator. I got the aftermarket one not the Mercury. Mercury is nuts 500 bucks is too much. At 100 hours I had a over heat problem. Turned out to be the bearing on the l-drive shaft fell apart. This caused the drive shaft to bind and rub sideway killing the pump the houseing and bearing in the lower unit. All of this cost a lot of money and time.<br /><br />Here is the real problem you will have. You will run into a lot of dealers, people that tell you give up throw that **** away. Also everything to fix that drive part will cost some money and Mecury is starting to stop selling replacment parts.<br /><br />I really like the l-drive simple, light and quiet powerful. As for putting another power head not too sure. I think any of the chrysler/force motors of the same hp will work. Before I rebuilt the force I looked in to putting on a 150hp johnson not even close. What stoped me was the drive shaft. <br /><br />Anyway I hope I did not screw you up more. <br />Good Luck