engin tear down

[tkq23111]

I have a 1968 50hp thunderbolt ser=2454257.Iam doing a rebuild.I have disasembeld the engin and cleaned it all up,the exhaust side was bad full of crud,cylender walls are not bad,where the head gasket goes there are some chips.I was wondering if i shuld put some gasket seal just where the chips are and then the gasket .If so what sealent should i use.I know your not supposed to use sealent on the head but what if i only put where the chips are.The reson i started doing a rebuild is because cylender #4 ,psi only reads 40 psi ,the other three read 119.when i took it apart the rings where melted into the piston groves on one side.I cracked the Lower End Cap when taking apart ill include a picture ,could i reuse this part or get another and where can i get a used one .I have got a new piston,a complete seal kit and have cleand the piston chamber side of motor real good,i cleaned it but didnt hone it.the other side with the pistons on it i left everything alone .ive only blowen clean with air.the rings look good and pistons look good but a litle carbon on top of pistons.this is my first time doing this and the only experiance i got is reading poasts.ill includ pics and could anyone give me some pointers.ty all.

 

[merc850]

Re: engin tear down

A Mercury dealer sells PERFECT SEAL to seal the crankcase and it is good to put on bolts to stop them corroding. You will need gaskets for the exhaust/water jacket as well, as for the lower cap try your dealer,ebay,iboats etc.

 

[tkq23111]

Re: engin tear down

so i would use the pefect seal insted of a head gasket is that what your saying because i cant find a headgasket anywhere.if so is there a certain brand of pefect seal i need.ty all.please help im read to put back to gether.also i have a couple dings where it goes together will the erfect seal take care of it.

 

[carholme]

Re: engin tear down

tkq;

Do you have a parts list for your engine and if so, what p/n are you using to search for a head gasket?

Gerry

 

[tkq23111]

Re: engin tear down

this is where i looking http://www.crowleymarine.com/mercury-outboard/parts/395_11.cfm .ty

 

[carholme]

Re: engin tear down

tkq;

Your engine is a model:

1500108 MERCURY 1968 50 which uses this part listing:

http://www.crowleymarine.com/mercury-outboard/437.cfm

In this link, is it item 47 you are looking for?

http://www.crowleymarine.com/mercury-outboard/parts/437_13.cfm


Gerry

 

[tkq23111]

Re: engin tear down

Im talking about part numbur 1 in diagram.the CYLINDER BLOCK where it goes together.i dont know if a gasket is needed there .ty

 

[carholme]

Re: engin tear down

Well it is confusing as you keep talking about a head gasket but the only gasket on that side of the engine is item 47 which is the gasket for the block cover.

If you are talking about the joint between the crankcase and the block, there is no gasket there and definitely not a head gasket.

Gerry

 

[tkq23111]

Re: engin tear down

Im back at it again and looking to find a pdf manual.I have allready bought one a couple days ago but its the wrong one .can anyone tell me where i can get one .I have seen this sight but cant find it there.http://forums.iboats.com/showthread.php?t=309079
the motor is a 1968 50hp thunderbolt ser=2454257.Included are more pics.Im ready to put back together and need torque readings and
sequence.ect .ty

 

[carholme]

Re: engin tear down

tqk;

Here is a conensed version of the Clymer manual which should have the torques you require.

http://web.ebscohost.com/serrc/pdf?...8-a64b-54a4d1d3cd31@sessionmgr14&vid=4&hid=13

Gerry

 

[tkq23111]

Re: engin tear down

TIGHTENING TORQUES (All Models)
(All Values In Inch-Pounds Unless Noted)
Connecting Rod 180
Crankcase screws 150
Cylinder Cover, bolt & nut 100
Exhaust Cover 150
Flywheel Nut . 65 Ft.-Lbs.
Reed Screws 35-40
Spark Plugs 240
Transfer Port Covers 45-60



on this page are the numbers the page or the torque per square inch.ty

and carholme ty thats good info. http://web.ebscohost.com/serrc/pdf?...8-a64b-54a4d1d3cd31@sessionmgr14&vid=4&hid=13

 

[carholme]

Re: engin tear down

tqk;

The link you provided is not working but if these are the torques you are referring to:

TIGHTENING TORQUES (All Models)
(All Values In Inch-Pounds Unless Noted)
Connecting Rod 180
Crankcase screws 150
Cylinder Cover, bolt & nut 100
Exhaust Cover 150
Flywheel Nut . 65 Ft.-Lbs.
Reed Screws 35-40
Spark Plugs 240
Transfer Port Covers 45-60

The numbers beside the component is the torque range in in/lbs., except for the Flywheel, which you will see is in ft/lbs.

Gerry

 

[tkq23111]

Re: engin tear down

more pics of 1968 50 hp thunderboalt.

still looking where i can but pdf manual

 

[tkq23111]

Re: engin tear down

I am having problems findind a inch pound torque wrench. I went to sears,advanst auto ,lowes and home depo,and nothing.I converted it into pounds so i can use a foot pound torque wrenck.Can you tell me if this looks right.also i had to buy a crows foot wrench because torque wrench was to big.ty


1.connection rod . 180 inch pounds =15 ft pounds
2.crankcase screws 150 inch pounds =12.5 ft pounds
3.cylender cover,bolt and nut 100 inch pounds =8.33 ft pounds
4.exhaust cover 150 inch pounds =12.5 ft pounds
5.flywheel nut =65 ft pounds
6.reed screw 35-40 inch pounds =3.3 ft pounds
7.spark plug 240 inch pounds =20 ft pounds
8.transferport cover 45-60 inch ounds =5 ft pounds

 

[mr 88]

Re: engin tear down

Yes your math is correct..in lb to ft lb multiply by .0833 ft lb to in lb multiply by 12

 

[carholme]

Re: engin tear down

Though your math is correct, there is no way I would use a ft/lb Q wrench for the lower values unless it is a very high quality wrench and has been recently calibrated. Then you have the added problem of using the crowsfoot, which depending on the angle you are using it at can alter the value of the read torque.

For reference:

http://www.finishing.com/118/94_crows_foot_torque.shtml


Gerry

 

[tkq23111]

Re: engin tear down

Allmost done missing two peices the STATOR iteam # 12 on this page.http://www.crowleymarine.com/mercury-outboard/parts/437_4.cfm .Actually the stator might be on it so i included a picture,if not does anyone know where i can get one.second and i dont know if this can be interchanged with another one and if so can you lead me in the right direction.Iteam #12 on this page http://www.crowleymarine.com/mercury-outboard/parts/437_9.cfm ty all hoping to turn it over soon.

 

[tkq23111]

Re: engin tear down

can anyone help with the literature to do the timing on this motor.I have this. http://web.ebscohost.com/serrc/pdf?...-925f-ae962de8f9c6@sessionmgr13&vid=4&hid=104 but its all blurry.link might not work.

 

[oldman570]

Re: engin tear down

For parts try going to Old Mercury.com website through your browser. or CDI website for stator and recitifer. Check out sticky for Outboard Salvage Yards also.
Oldman570

 

[tkq23111]

Re: engin tear down

stuck on the control box,.pics included.I half way referbished the wiring,but did fixed the saftey nuterul swith that wast working also cleaneView attachment 133182d the hole control box up.The throtle cable piece that holds the cable into place was worn and not working and is my main reason for posting this.so i filled it in with rubber cement because thats all i had in hand and it didnt work so i boaght a stick of J-B STICK epoxy.what is your opinion