a "C" or not a "C".......that is the question. Johnson 30 HP '56?

[MidMichigan]

I have a Johnson motor I plan to put on the 14' tri-hull Mon Ark, but need to know the year. Having searched found a post about a '59 Johnson and the link http://www.old-omc.de/index2.html provided in the answer (thanks tashasdaddy) - don't see the "C". What does the C stand for? Mine says Model RDE 18 C, and serial No 1459324. I plan to follow the advice to awaken the old motor http://forums.iboats.com/showthread.php?t=158086 and resist the urge to pull the rope and fire it up.

I need to order a manual to find out the impler to replace, any gaskets, plug recs, fuel mix, lower end oil, , etc. but before I do - want to make sure that it is a '56.

Anyone have this motor - will it push a fiberglass trihull of 5-600 lbs, fuel and other supplies, and 4 people? I'm new to this forum and to boating an apprecaite any help. Take care - TJ

 

[Joe Reeves]

Re: a "C" or not a "C".......that is the question. Johnson 30 HP '56?

Re: a "C" or not a "C".......that is the question. Johnson 30 HP '56?

RDE-18C ia a 1956 30hp Johnson. Use CHampion J4C or J6C plugs gapped at .030. Mixture can be 50/1 (TCW-III Oil) on that model. Grarcase lube is HiVis 80/90w, available at Wal*Mart, K-Mart, your dealership etc. Gasoline octane 87 is fine. Points set to .020.

 

[david_r]

Re: a "C" or not a "C".......that is the question. Johnson 30 HP '56?

Re: a "C" or not a "C".......that is the question. Johnson 30 HP '56?

but what is the suffix "c"?

mines an r is that for "race"?

 

[MidMichigan]

Re: a "C" or not a "C".......that is the question. Johnson 30 HP '56?

Re: a "C" or not a "C".......that is the question. Johnson 30 HP '56?

Joe Reeves - thanks for the info and quick response.

David_r - yes i'd still like to know what the "c" is and the difference between RDE 18 and RDE 18C.

I'm not sure if you were being sarcastic to someone new to boating or if there realy is an "r" suffix- but it was a serious question so I don't ask for the wrong parts if there was a difference. In the next year ('57 they apparently went to 35 hp RDE 19, and the RDE 19c was the following year '58 - so it stands to reason that the C is there for a reason and that they didn't have too many laying around and decided to use them on model numbers)

 

[F_R]

Re: a "C" or not a "C".......that is the question. Johnson 30 HP '56?

Re: a "C" or not a "C".......that is the question. Johnson 30 HP '56?

That little trick they pulled in 1957-58 was an exception to the rule, so don't pay any attention to it because it doesn't apply to your motor.

Johnson started each years' production run with a letter-suffix to their model numbers. The letter seemed to be picked at random, but probably was somehow related to the final engineering design as it was released for production.

That letter-suffix may stay the same throughout the entire model year and mean absolutely nothing. However, if there is an engineering change during the year, the letter-suffix will change to indicate that. It only matters if you need to replace the part that was affected by the change. The parts book will indicate that difference.

 

[Joe Reeves]

Re: a "C" or not a "C".......that is the question. Johnson 30 HP '56?

Re: a "C" or not a "C".......that is the question. Johnson 30 HP '56?

As F_R states, that last digit, in your case "C", is simply a factory run identification digit. Ignore it.

 

[56 rude]

Re: a "C" or not a "C".......that is the question. Johnson 30 HP '56?

Re: a "C" or not a "C".......that is the question. Johnson 30 HP '56?

RDE-18C ia a 1956 30hp Johnson. Use CHampion J4C or J6C plugs gapped at .030. Mixture can be 50/1 (TCW-III Oil) on that model. Grarcase lube is HiVis 80/90w, available at Wal*Mart, K-Mart, your dealership etc. Gasoline octane 87 is fine. Points set to .020.

Did the 30 hp of 56 not use plain bearings on the wrist pin end of the con rod?I specifically asked my old time johnny dealer a lot of questions about the old motor as i have one also and he told me to run 24 to 1 as they like their oil.

 

[56 rude]

Re: a "C" or not a "C".......that is the question. Johnson 30 HP '56?

Re: a "C" or not a "C".......that is the question. Johnson 30 HP '56?

MID -MICHIGAN points condencers and coils and waterpump impeller are all the same as a 1970 33hp evinrude ski-twin as ive just done that swap from the 30 to the 33 as the 30 is very ill and had all new parts and they bolt up directly no problem.all the parts your looking for are still available up to and including a cluch dog if needed.got my doggy from the johnny dealer directly .if your looking for anything particular in the way of restoration parts (hood ,lower etc) feel free to pm me as im concidering parting ways with the 30 .just did a 70 plus mile river run with the 33 hp and she never missed a beat!the 33 is butt ugly as far as im concerned and i like the looks of the 30/35 50,s motors way better ,as a matter of fact any johnny from the 50,s looks cool!

 

[david_r]

Re: a "C" or not a "C".......that is the question. Johnson 30 HP '56?

Re: a "C" or not a "C".......that is the question. Johnson 30 HP '56?

David_r[/B] - yes i'd still like to know what the "c" is and the difference between RDE 18 and RDE 18C.

I'm not sure if you were being sarcastic to someone new to boating or if there realy is an "r" suffix)

sorry wasnt trying to be sarcastic, just trying to make a funny. it reminded me of when i was a little kid and thought r meant race. but mine really has an r--115TL79R

like Joe and F_R and everyone else has said "ignore it"---i looked for a long time at my different years, parts, etc...and couldnt find exactly what the suffix meant. im an auto mechanic and ive worked in parts and the prefix and suffix are significant. but apparently the engineers who built these little gems have somewhat of a sense of humor. i could understand if there was a reason but on the ones that dont have a difference its confusing.

 

[tx1961whaler]

Re: a "C" or not a "C".......that is the question. Johnson 30 HP '56?

Re: a "C" or not a "C".......that is the question. Johnson 30 HP '56?

The gasil ratio shoud be 24:1
http://forums.iboats.com/showthread.php?t=158072

 

[MidMichigan]

Re: a "C" or not a "C".......that is the question. Johnson 30 HP '56?

Re: a "C" or not a "C".......that is the question. Johnson 30 HP '56?

Thanks guys

also it came with another one model RJE 18 - missing lower end and pretty rusted - are the parts interchangable RDE/RJE ? they look the same - maybe Johnson had some extra "J's" to get rid of in '56 too. I was going to keep it around if the same - or would work for part - but don't want to be a packrat if not or wastse time trying to clean it up and guess what is worth saving or keeping.