1971 johnson 4hp cowl gasket problem

[Stickler]

Hello, new to the forum hope i posted this in the right area, anywho my 1971 4hp johnson 4W71D came with a cowl but no gasket, so i couldnt use it. I recently ordered one from the only person who seemed to have one online, and when i put it on the cowl it fit well, but when placed on the motor it fits really tight and doesnt sit well at the rear of motor so im unable to lock down the cowl, anyone else done this and run into same issues, or any suggestions to solve problem, also any pics of a factory installed seal might help as the original was not there when i got it. thanks everyone

 

[TN-25]

Re: 1971 johnson 4hp cowl gasket problem

First of all, welcome Stickler! I do not have the definitive answer to your dilemma, but I did try to do some research on it.

I looked at the parts catalog for both the 1971 Johnson 4 & 1971 Evinrude 4. The cowls themselves have a different contour to them, as do the corresponding pans that they sit in. The rubber gaskets have different part numbers, due not only to the color of the rubber, but also to the slightly different shaping. Refer to the attached pictures. From the parts catalog diagrams it appears that the rubber gaskets seem to have a different thickness and cross section, although that is difficult to establish without actually having the cowlings side by side for comparison. I myself have a 1971 Evinrude 4.

Please refer to the color pictures of the Johnson & Evinrude 4s. Since my digital camera battery is missing and my computer does not want to read from any external mass storage device (camera or hard drive) I have resorted to borrowing a couple of classified ad pictures. On the Evinrude, note the way the cowl gasket is secured to the lower edge of the cowl with large staples. I am not sure that most people have access to such a stapler. Since your original gasket was missing, and presumably the staples as well, I would see if I could somehow get a hold of some kind of industrial strength stapler. The existing holes from the original staples will be visible on your cowl. Failing that, an alternative might be to use some adhesive. The factory used staples for a reason I assume. Adhesive is more of a ?place once and it is there for keeps? affair, plus it may make a mess for gasket replacement in the future.

If you are referring to the online vendor that is selling the replacement gaskets, he does actually say that you need to verify that they are correct. From my own experience with him concerning rubber cowl gaskets for a different motor that I have, it was perfect, though I did need to trim mine to length. In your case you should try to see if anything is interfering with the gasket, such as the rear latch mechanism. I know that on my Evinrude 4 the rubber gasket is carefully trimmed from the factory at the front where the flat hook secures the front of the cowl to the slot in the pan. Anything like that needs your intuition & observation to see if anything is causing interference. I wish that I had a Johnson 4 cowling to look at specifically. That would tell us if the factory did any trimming to make things fit.

I hereby invite anyone else with an original cowl for a 1968 Johnson 3 or 1969 ? 1978 Johnson 4 to post pictures of their cowl gasket as installed on the lower edge of their cowl.

Keep us posted Stickler. Hopefully you live up to your namesake!

 

[Stickler]

Re: 1971 johnson 4hp cowl gasket problem

Hi there TN-25, really appreciate u taking the time to upload the photos and respond to my post. My cowl did have several holes around the perimeter of it, when i restored the cowl it was stripped down to bare fiberglass ,and like a dope:facepalm:, i filled the holes with fiber glass filler before i primed it, (i jazzed it up a bit by upgrading the color from white to Duponts ford pearlescent white , new decals ,and then cleared over , wet sand and then polished),had to be done.
The gasket sat in the groove ok when i placed the gasket around the pan by itself , but i noticed in the corners had no gap, so if i placed the cowl onto the gasket that is already sitting in the pan groove it would be a no go.So i put gasket on cowl and cut notches in each corner on the inside so it wouldnt bind,didnt see any way around it, so im assuming a variation of that was done in the factory. the staples make sense due to the fact that the gasket tends to pull away from the cowl in areas likely not helping my fit.One thing i tried was holding the gasket in place, putting the cowl on the motor and tapped the cowl down so it would sit in its groove , i got it to go on somewhat and pulled the lever to lock it down ,but as i did this it was really tight and the area where the hook is on the inside of the cowl actually caused the fiberglass to bow inward when locked down, shouldnt be that tight.
So im really wondering if it is correct , i did email the guy i purchased from before i ordered it to confirm right part, and concluded this was the part, we both agreed and i ordered it. The only thing is that off the the cowl it fits well,may just require more fine trimming in areas and definetly staples as you said, just need to find a way to staple without worrying about cracking the 31 year old fiberglass, probably more forgiving in 1971. So i guess i need to secure it properly, doesnt fit nearly as snug against the cowl like Photo #3,which is my motor exactly.Securing properly to cowl will be my next step, as well as looking for areas to trim,also an image of the front of a cowl where the tang is that slides into the notch in the pan(front),may also not be trimmed right.
Once again thanks for the photos and the ideas/info, really appreciate it,any other ideas that may come to mind fire them my way . Thanks again,Stickler.

 

[AlTn]

Re: 1971 johnson 4hp cowl gasket problem

I recall seeing a pic of the cowl gasket being held in place while the adhesive dried by what appeared to be 50 wooden clothes line pins...fwiw

 

[TN-25]

Re: 1971 johnson 4hp cowl gasket problem

Looking more closely at the pics I have to conclude that in the case of your Sea Horse you should not have to make relief cuts in the rubber. I have to ask, is the gasket installed correctly? It should only be thin rubber that wraps around the lower edge of the cowl and it should not appreciably add to the thickness of the fit between the cowl & channel in the pan. Is the clearance issue only when you attempt to cinch the cowl down with the latch? If so I would pay attention to the molded extrusion along the upper part of the gasket. Take a close look and report back.

BTW, your motor is supposed to be a 50:1 mix motor, but from what I have seen & read it may be better to run your motor a little more rich in the oil department due to the only partial adaptation by OMC to enable the 5.28 c.i.d. powerhead to run on reduced oil. After I awaken my long slumbering, low hours 1971 OMC 4 I will be running it on 24:1 to 32:1 gas / oil mix to ensure adequate lubrication. These powerheads really date back to the 1952 3 horse joint-venture Johnson / Evinrudes. With proper care they should last practically forever, assuming continued consumable parts supply.

 

[kodibass]

Re: 1971 johnson 4hp cowl gasket problem

Hi' stickler
can I ask a question of you as it sounds like you have already researched this part, What adhesive will you be using. I just glued mine with marine goop and it did not do well, Also i bought a large bag of plastic clamps in the tool isl at wally world for $5 it had plenty of small/medium sizes perfect for clamping the gasket in place to dry. cheers

 

[Auxlarry]

Re: 1971 johnson 4hp cowl gasket problem

3M weather strip adhesive works great and is available in most auto parts stores.

Larry

 

[Stickler]

Re: 1971 johnson 4hp cowl gasket problem

Hi all ,thanks for the responses, (TN-25) your probably right about the relief cuts not being necessary, it is installed correctly on the cowl,when i set it in the channel ,the seal really doesnt want to sit without any force put on it , but even then it tends to ride back up and out of the channel, what im gonna do is take some pics and upload them so you can see whats going on , and then there may be some areas that you guys may see where it may need to be trimmed up(Apicture is worth a thousand words).

As for fuel mix i do use 24:1 , before i ever used it i researched this and came across conflicting awnsers , from what i gather they dont have needle bearings and therefore require more lubrication,runs a bit smokey, but to be expected, better to have too much oil than the consequences of not enough oil in my opinion.I use Lucas TCW3 low ash marine 2 stroke oil.

As for attaching the gasket , i would agree with (Auxlarry) 3m weatherstrip is a good product and will be my first choice when i attach the gasket , ill let you know how it goes when i try it.

Again thanks for the help guys , ill post pics and be in touch soon, Stickler.

 

[sutor623]

Re: 1971 johnson 4hp cowl gasket problem

I have both models if you need any more pics or ideas on how they are attached.

 

[Stickler]

Re: 1971 johnson 4hp cowl gasket problem

thanks for the photos (sutor 623) would u be able to send me a photo of the front of that johnson cowl it looks as if they removed alot more of the gasket below the little johnson emblem than i have , iam assuming that is the original untouched gasket, that could be part of my problem,every little bit helps, thanks again.

Stickler

 

[sutor623]

Re: 1971 johnson 4hp cowl gasket problem

Yeah man, if you can hold off til this evening. I can have some pics up around 7:30 tonight.

 

[Stickler]

Re: 1971 johnson 4hp cowl gasket problem

That would be great ,really appreciate u taking the time ,hopefully ill have some photos of my cowl up this evening as well.

 

[sutor623]

Re: 1971 johnson 4hp cowl gasket problem

Okay sorry man, Ill have them up in a few. My camera battery is being a snob....

 

[Stickler]

Re: 1971 johnson 4hp cowl gasket problem

Hey all ,i tried uploading my pics but to no avail, im going to keep working on it , dont know why they wont upload, but ill try to figure it out.

 

[Stickler]

Re: 1971 johnson 4hp cowl gasket problem

Hi everyone , just a quick update, tried attaching the seal with 3M weatherstrip and about 20 clamps holding it down,when cured and clamps removed ,it started peeling away , it took me 2hrs to get the glue all off. So the next thing i tried was a good quality rtv silicone ,same thing, removed clamps and some areas bonded and some didnt , anyway it is not going to hold up.Now im going to try a hot glue that a friend said will bond well , used for dent removal , he talked me out of using gorilla glue cause he said it would be a disaster to remove if it didnt work.So anyway ,this is what i have tried so far, if anyone has any ideas or photos fire them my way thanks again ,Stickler.

 

[AlTn]

Re: 1971 johnson 4hp cowl gasket problem

hmmm... a friend of mine used 3M weatherstripping adhesive on a 9.9 cowl gasket and it worked well...could you tell if it was peeling away from the fiberglass or the vinyl?,rubber? gasket material?

 

[Stickler]

Re: 1971 johnson 4hp cowl gasket problem

From what i can tell its pulling away from the cowl not the rubber seal, i should mention that my cowl is repainted and decaled using automotive paint and clear coat , so where the gasket is glued on the outside its adhering to paint not bare fiber glass, but on the inside of the cowl it is bare fiberglass and adhering just as poorly.

 

[AlTn]

Re: 1971 johnson 4hp cowl gasket problem

thanks for that info, Stickler. I dunno, maybe ask some body shops in your area what they use?

 

[Stickler]

Re: 1971 johnson 4hp cowl gasket problem

I managed to get these pics uploaded of my cowl ,the gasket is just placed on there loosely,the front of the cowl in pic 3 the gasket below the sea horse eblem needs to be cut but i would like to see a pic of one so i know exactly how much needs to be removed, the metal tang wont slide into its place on the pan due to the gasket, any images would be greatly appreciated, thanks,Stickler.

 

[sutor623]

Re: 1971 johnson 4hp cowl gasket problem

Shoot man, what address do I need to send mine to? That joker looks GOOD!