Perfect Seal on Bolts

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tmasloske

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I see in my service manual under the tune up section that it says to dip all bolts and screws in perfect seal #4. Would this include the cylinder head bolts?

In some areas of the manual it will specify when to dip bolts into gasket sealing compound (Impeller housing screws) and in other sections there's no mention.

Should all bolts and screws prone to corrosion be dipped?
 
Gary H NC

Gary H NC

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Re: Perfect Seal on Bolts

Not sure about the head bolts.I noticed my manual says to use OMC thread locker on some bolts and others call for the sealant.
DHadley or Ezeke should know and chime in on this.

All of my lower unit and many other bolts i dip in sealant.
 
T

tmasloske

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Re: Perfect Seal on Bolts

I recently replaced the cylinder head and cleaned up the bolts with a wire brush and sprayed WD40 on them. Some of the bolts were pretty rusty. I'm thinking if I used the OMC gasket sealing compound on the bolts it should help prevent further corrosion.
 
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tmasloske

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Re: Perfect Seal on Bolts

Anyone know if I should put OMC sealing compound on cylinder head bolts?

Thank you in advance.
 
Gary H NC

Gary H NC

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Re: Perfect Seal on Bolts

I just read through my factory service manual.It says to use a light coat on the head gaskets unless the gaskets are marked "do not use sealant"
As far as the bolts i would put a light coat on them.
The manual does not say to use it on the bolts or not.

Did the bolts look like anything was used on them before?
 
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tmasloske

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Re: Perfect Seal on Bolts

When I took off the cylinder head, the gasket was not original but a Sierra. Don't know if the person who put that on put sealer on the bolts or not. They just looked rusty.
 
Gary H NC

Gary H NC

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Re: Perfect Seal on Bolts

I would go ahead and use it. Its better than seizing up a bolt and messing up threads.
The books says to torque the bolts to specs then run the engine up to normal temp then re-torque the bolts.

I sent a message to one of our Johnny-Rude pros about the sealant.
Maybe he will get back to us.
 
T

tmasloske

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Re: Perfect Seal on Bolts

Thank you.

I'm thinking a thin coating shouldn't hurt and will help prevent further corrosion in the future.

This is for my "new" '68 Evinrude 18 HP. What a great hobby!
 
Gary H NC

Gary H NC

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Re: Perfect Seal on Bolts

I know it gets fun...lol!:D

I have my lower unit and powerhead in the garage right now.

Will be doing head gaskets and thermostats on the powerhead.
It had to come off anyway to replace the base gasket.

My lower unit is ready for new paint...sanded on it until midnight last night.
Waiting on UPS to deliver my paint today...:)

Something to do on cold evenings in the garage.I need to go out there and get some heat going so i can paint this evening....
 
bowman316

bowman316

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Re: Perfect Seal on Bolts

I just replaced my head gasket, and did not put anything on the bolts. The bolts go through the middle of the head gasket, if i remember correctly, or they are on the outside of the gasket.
either way,
the bolts will not let water leak through the threads, they are not involved in the watertight seal in any way,
they just provide the pressure to keep the seal tight.
it is not like water, or gas, is going to leak through the bolt holes.
 
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Dhadley

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Re: Perfect Seal on Bolts

Personally I use OMC / BRP Gasket Sealing Compound on head bolts, in fact all bolts except rod bolts. We're in salt water and it will, over time, make a difference. I know that in theory salt should not get in bolt holes or threads but apparently salt didn't get the memo.
 
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HybridMX6

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Re: Perfect Seal on Bolts

Dhadley said:
Personally I use OMC / BRP Gasket Sealing Compound on head bolts, in fact all bolts except rod bolts. We're in salt water and it will, over time, make a difference. I know that in theory salt should not get in bolt holes or threads but apparently salt didn't get the memo.
Click to expand...

I hear that. I'll be doing that with all the bolts also (except the rod bolts since they're in the engine).
 
Gary H NC

Gary H NC

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Re: Perfect Seal on Bolts

Thanks DHadley! I knew you would come through on this question..:D

I have used the sealant on all the other bolts and so far it makes it much better if you have to remove them.
 
Benny1963

Benny1963

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Re: Perfect Seal on Bolts

i use it on all bolts except rotating assembly.
and iuse light coat on head surfae and gasket regardless of there sealer or not .dhadley answered this question for me last year and as usual he was right,
 
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