Force 85hp head bolt specs

krobertson

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Anyone have the head bolt tq and pattern specs for an 85 hp force. It is an 89 L dive # H085LD89A please?
 

krobertson

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Re: Force 85hp head bolt specs

Also...the bottom head bolts by the water exit...do they need to have sealer on them or just tighten and go?
 
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Frank Acampora

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Re: Force 85hp head bolt specs

No sealer required but it is wise to use anti-seize compound, silver color, Nickel. Do not use copper.

head bolt torque is 225 INCH pounds in a spiral pattern outward from the center. If a new gasket was used, loosen and re-torque after running the engine for about 1/2 hour-- on the water, not in the driveway.
 

jerryjerry05

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Re: Force 85hp head bolt specs

No inch pound wrench.It's 20 ft pounds.
Start at 15# the 17 then finish at 20#
I've found using anti sieze in salt water, turns it into perm sieze.
The stuff won't let go if mixed with salt water.
I've heard of mixing it with marine grease at 50/50
Or just use marine grease.
Where in Fl.?
 

krobertson

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Re: Force 85hp head bolt specs

JerryJerry....I am in Lake City north of Gainesville. Was going through all the water jackets and such when I started overheating at higher RPMS or WOT. Found some old impeller here and there but problem was new impeller I just put in. One fin was gone....2 others breaking. But having the head off was good because I pull about 6-8 pieces of rubber from jackets around cylinders and also added a telltale.
 

pnwboat

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Re: Force 85hp head bolt specs

You may have some rubber tube "flow diverters" between each of the cylinders. You want to leave those in place. They direct the flow of water around the outer perimeter of the water jacket that surrounds the cylinders. Below is one pictured in the yellow circle.

IMG_0591.JPG
 

krobertson

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Re: Force 85hp head bolt specs

OK so when I was using a pick to get our rubber pieces all around the cylinder water jackets I noticed the humps in the water jackets. But there is no rubber tube diverters.....this engine has had work before so what are those and I guess you need them ha?
 

krobertson

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Re: Force 85hp head bolt specs

Also...just looked it up on boats dot net to check parts diagram. I did not see that on any parts breakdown either?
 
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pnwboat

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Re: Force 85hp head bolt specs

I've not taken an L-Drive block apart, so I can't say 100% for sure. I can say that every 3 and 4 cylinder block that I've disassembled has had them. Yes they are not noted on any parts breakdown that I've looked at. If you think about it, without them, the water may not flow evenly to the lower cylinders. The water enters the cylinder water jacket at the top left. Without the diverters, it may just flow between the top cylinders and not very evenly to the lower cylinders. I would say that they should be there. Here is a diagram of the water flow. It's not specific to the L-Drive, however, if I were a betting man, I would say the L-Drive is the same. Disregard the water pressure relief valve in the diagram. That is only applicable to the earlier Force motors. Later models did away with it. It was more trouble than it was worth.

water flow.JPG



I've had blocks where they were in such bad shape that I had to replace them. Just used I believe 1/4" hose from the autoparts store. Take a rod and measure the length of the cylinder and cut to length.
 

jerryjerry05

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Re: Force 85hp head bolt specs

They weren't in the last motor I rebuilt.
Not sure about the others?
Pics don't show how deep/long they are?
 

krobertson

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Re: Force 85hp head bolt specs

So are we talking like fuel line will do the trick? Once you get it in place I guess there is no slippage? Not to bash Force but that is a poor design. That should have been hard casted when making the cylinders....not an after thought. I will try to get this top side back together today and wait on my water pump to show up....stay tuned!
 
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pnwboat

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Re: Force 85hp head bolt specs

Yes, I don't even know if it was fuel line. Maybe vacuum line or something similar. Large enough diameter to get a good snug fit, but small enough to be able to push it down the slot or gap. Like I said, can't remember the exact diameter I used, but I believe it was about 1/4". They run from the top edge of the cylinder all the way to the bottom of the water jacket. Basically act as a dam to prevent water from flowing through the gap between the cylinders.

I'd have to agree with you on the design. Not sure what they had in mind with that design.

Interesting that Jerry has seen blocks without them. Maybe some of the other folks on the Forum can chime it. There's probably pro's and con's either way, with or without them.
 

jerryjerry05

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Re: Force 85hp head bolt specs

That little piece of rubber.It's used by Mercury and some of the others too.
The ones I didn't see??
The motor could have been overheated and then washed away??
They were in my Merc 225.
 

krobertson

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Re: Force 85hp head bolt specs

But they do need to be between both cylinders...this is what I will try then! Impeller comes in tomorrow. I will get the 1/4 line when I pick it up and I will put her back together and hopefully life will be great again!
 

krobertson

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Re: Force 85hp head bolt specs

pnwboat....when looking at your water flow diagram I do not think that is the same. I have a thermo at the top of the motor (on head)#1 cyl and at the bottom of the motor #3 cyl is an water out. Attached is a pic of my head bottom side. Not sure about the movement of the water...but I do see notches between cyl water jackets.
Force Head.jpg
 
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pnwboat

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Re: Force 85hp head bolt specs

It's the same...The pipe looking thing on the diagram on the right side actually represents the cylinder head.

In your picture (post #16), the opening at the bottom (by the thermostat) is where the water enters the head after going through the thermostat. It flows through the head and exits at the opening at the top of your picture. From there it passes through a passage in the block and the adapter plate and goes out the exit hose attached to the exhaust cover (L-Drive).

Here is a picture of a 4 cylinder head assembly with the cover removed. Not sure if you were aware of the water passage in the head. Thermostat is located to the left in the picture. Water exit is the red arrow on the right. The cover is held on with three small bolts (3 cylinder) next to each spark plug hole (once you remove the head bolts). There is no gasket, just silicone RTV

water jacket1.jpg

It surprises me that both you and Jerry have blocks that do not have the flow diverters. I've never seen one without them. I had always "assumed" that they were in all blocks. Now I'm questioning that "assumption". So I'm not 100% sure if they are actually necessary.

Regardless, I believe that you have found the reason why your motor was overheating. The broken impeller and bits and pieces of impeller blade in other parts of the water passages. I'm beginning to doubt that the lack of the flow diverters has anything to do with the overheating.

NOTE: If you decide to install the flow diverters....when I stated 1/4" line, I was referring to the "outside" diameter of the hose. When you go to the parts counter, and specify 1/4" hose, the parts person will be going by the "inside" diameter. It'll be too big. You have to explain exactly what it is you're looking for.
 
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krobertson

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Re: Force 85hp head bolt specs

Ya I already got the 1/4 hose and that was my exact thought. I couldn't bare telling the guy to get more so I will go else where. Besides NAPA is a pain to work with here in Lake City. So I just set my head cap on my head and I will let the RTV set before messing with it again...couple hours should be fine. So should I try it without the diverters? I can tell you this motor has had work before. So they may have removed them but no idea. Maybe I should leave them out and see what happens?

Anyone else with a Force L Drive have the water diverters around they cylinder jackets between each piston?
 

pnwboat

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Re: Force 85hp head bolt specs

I'm not 100% sure, but based on what Jerry has seen and your situation, I would try it without them. Not really that hard to remove the head and install them if absolutely necessary.
 

krobertson

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Re: Force 85hp head bolt specs

OK guys here it is...I took the pics...my cylinders have built in diverters? Take a look-see at the pics below. I did not add the hose. Waiting on impeller tomorrow to test. All cylinders are sitting between 121 lbs and 132 lbs of compression. Lowest being bottom and highest being top or #1. Same as when I first got it...so the overheating didn't cause issues. And they cylinder walls were still good. Funny how all motors seem to be that way #1 highest and the furthest from top the lowest. Any who take a look and tell me what you think.
cyl1.jpg
cyl2.jpg
cyl3.jpg
 
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