1977 35 hp Service bulletin

[Jogin]

Hey everybody, I just recently was given a 1977 evinrude 35 hp outboard, and I was talking to a person I trust well, he was saying that there was a service bulletin on this gearcase. We cant seem to find the service bulletin, however he remembers there being one saying that you need to drill holes into the gearcase for extra water intake, I normally would not want to do something like this but I also trust him too. He also said that it may have been put out due to the updated impeller housing. I have the origonal in mine but would like to make sure everything is good to go before I run it anymore. So if anybody can locate this service bulletin or has other information on it I would appreciate you sharing it with me very much.

Thanks,
Jogin

 

[HighTrim]

Re: 1977 35 hp Service bulletin

Im not sure about a bulletin, but I have that motor in both the 35 and 55hps, and they both run extremely well, in perfect operating temperature. I have not modified the gearcases in any way. If your cooling circuit is operating as it should, I would leave well enough alone. I would be curious to read that bulletin if it exists though. Is he saying that the bulletin reccomends drilling more holes in the water intake screen?

 

[Jogin]

Re: 1977 35 hp Service bulletin

He said that there would be a couple holes drilled right underneath the antiventilation plate for both chambers. I have a feeling it has something to do with an updated housing, which I do not have, however he believes that the reason he is remembering this is because that was the first year for that era of style of motor. He also said it was only on the 35's. Do you know where a guy can look up old service bulletins on this year and model of outboard? Also I am sure it does not have cooling issues currently since there are no signs of it and it has great compression. I would just like to get this done before I find a boat for it and then wont have to worry about the issue ever.

 

[HighTrim]

Re: 1977 35 hp Service bulletin

Some of the guys on here keep the bulletins, I personally dont have that one. Nothing that I have ever heard of either. Might get lucky and someone reading has it. Could also visit the dealer. Get some more input on it though before you go drilling your gearcase. Otherwise you may be searching the online ads for gearcases this summer.

 

[boobie]

Re: 1977 35 hp Service bulletin

The holes your talking about are drilled at an upward angle above the water pump screens into the pick up passage. They were for extra water if the screens got clogged. When ever you run a mtr with these holes in on muffs you should put duct tape over them to keep from sucking air. I remember a service bulletin on this but I looked at mine and can't find it. If I do I'll get back to you. If it's working okay now don't start drilling!!!

 

[F_R]

Re: 1977 35 hp Service bulletin

What screens? There are only a series of drilled holes to admit the water. I am not aware of a bulletin on them , but it may very well be there was one. That motor was a "lemon" if you tried to run it within 100 feet of a water weed. Weeds would obstruct the water intake and the motor would burn up. Extra inlet holes certainly wouldn't hurt, if properly located.

The design was changed eventually, when the inlet was moved to the sides of the gearcase---with screens. That design is very good.

 

[boobie]

Re: 1977 35 hp Service bulletin

I "sit corrected". There are bulletins out there though on over heat probs for that mtr. Why don't you dig into yours and see what you can find? Let us know.

 

[EN2]

Re: 1977 35 hp Service bulletin

Years ago a freind of mine had 1976 35hp Johnson brand new. On his first outing it overheated and seized. Took it back to the dealer and they gave him a new one. The told him that there were some coolant passages that had casting flashing not removed. I dont know if it was in the lower housing or the block. The new motor he got was fine.