MarineEngine.com - Your online store for all types of marine engines and boat parts.
PHONE ORDERS
Monday - Friday
9:00 AM - 5:00 PM EST
Click for TOLL-FREE Number
Online Checkout
Special $9.95 Flat Rate Shipping
(800) 209-9624 | Home | Contact | Shipping | Returns | Cart View your shopping cart.
Part Number Search
Shop by engine/drive part number.
Original & matching parts for sale.
Manuals & Accessories
Shop by description, item number
or manufacturer's model number.
Boat Repair Forum Boat Repair Forum   Boat Video Gallery Video Gallery
   
Results 1 to 14 of 14
  1. #1

    Question '79 Renken Bowrider (good shape) - "Fishing Boat Project" - *NEED HELP WITH '72 JOHNSON 100HP*

    I have read this site numerous times, looking for answers to problems I encounter and so forth... But I've never posted on this forum, ANY HELP IS GREATLY APPRECIATED!!!!

    I want it to be known that for about 8 years I owned a '74 Wellcraft V20 with an '82ish (I BELIEVE! - cant recall actually, but I'm pretty positive it was an early 80's!) Evinrude 140hp V4. I pretty much rebuilt the boat, but the motor had just been rebuilt when I purchased it and ran exceptionally well for the years I owned it! I DO KNOW quite a bit about motors, as I have helped rebuild a 25hp (tiller motor - Mercury Mariner) and TONS of ROAD vehicles....

    That being said... Yesterday I bought a 1979 Renken Bowrider. I know the boats don't have the GREATEST name in history, but hey! I got the boat (in pretty mint condition), trailer (IN MINT CONDITION!), and a '72 Johnson 100hp for a cool $150!!! I couldn't turn it down! ESPECIALLY after I jumped a battery to it and got the starter to turn the motor over! That being said, I have just a few minor questions for yall... if you don't mind answering them for a fisherman that's ready to get back out on the bay!!

    The model of the motor is the 'ol 100ESL72R - just for reference! From another post I read, I now know that the compression should be around 100lbs per cylinder (3-4 lbs: give or take). I've also learned that there is a purple wire on the "terminal block" at the top of the "exhaust baffle plate area" (between the cyl. heads). From my understanding, it goes to the powerpack and should read a good 12v's. I will be in the process of conducting these test within the next cpl days! I also know that the plugs should jump a 1/4 gap, correct?

    The boat AND motor have been sitting for ABOUT 15yrs! The guy bought the boat and motor "new" from a dealership, once the throttle stopped working he covered it and ditched it for another, BRAND NEW boat... He had plans to rebuild the boat w/ his son, but obviously never got around to it!

    Now that that's out the way, I just wanted to ask a couple questions that should be relatively easy to answer for some:

    1. Will the motor turn over by just jumping it from a car (without a battery in the boat itself)? I don't believe it will, as I tried and the starter just spins! It WILL raise up and catch the flywheel OCCASIONALLY but instantly stops, for what I'm guessing due to a NON-SOLID connection... My Evinrude would do the exact same thing!

    2. Where should I begin on the motor?! Haha... I really don't want to rebuild the ENTIRE motor if it's not necessary! What are some common problems with these motors? Should I get a new powerpack for it? He said it was replaced right before it sat for many years....

    3. Can I use a newer "cable driven" (Teleflex) turning system on this old motor?? As the boat and motor is so old, it still has the "pully system" all hooked up! Which still works rather well, I just don't know if I trust it! What's the thoughts on this?

    4. Also, since the throttle "failed" on the previous owner (though I don't see ANY damage with the remote/controls?!).... Can I use a newer control on the older motor? Again, any thoughts on THIS?

    ...... And that's really all I have to ask honestly! Haha... As I'm sure the new battery, than checking the compression, spark and fuel (once I connect the tank again - as it was removed to keep ANY water out of it) will answer a lot of questions! The prop spins freely, the flywheel turns freely as well.... I'm sure I'll have to take the carb off and thoroughly clean it inside and out! I guess it's just a matter of getting the motor to run/turn over first and than go through the check list of what needs to be replaced huh?!

    Any info you can throw my way will be GREATLY appreciated!!! I miss having a boat to run around the Chesapeake Bay in!!! I miss everything about it, its been ABOUT 7 years since the Wellcraft.... that's the longest I've EVER gone without having a boat to jump in and go fishing, skiing, tubing and just cruising!

    Sorry if I've over explained my situation to the extent of not wanting to answer my questions!!! lol... I just wanted everyone to know that I am a good guy, my background and I'm a person who grew up on the water! I just want me a reliable boat to teach MY lil one the ways of the water, as my Grandfather did with me!!

    Much appreciation for all of the knowledge and what I've learned so far.... A direction to the land (water) of freedom, would be a blessing I've prayed about for a LONG LONG TIME!

    Yours Truly and Thankfully!!!! Name's Chris!

  2. #2
    Join Date
    Sep 2010
    Location
    ontario
    Posts
    9,581

    Default Re: '79 Renken Bowrider (good shape) - "Fishing Boat Project" - *NEED HELP WITH '72 JOHNSON 100HP*

    It is an electric shift motor and no controls after 1972 had that feature.-----------You would need a control box for -----------HYDRO-ELECTRIC SHIFT -----------with a big round black plug.--No others will work.

  3. #3

    Default Re: '79 Renken Bowrider (good shape) - "Fishing Boat Project" - *NEED HELP WITH '72 JOHNSON 100HP*

    Quote Originally Posted by racerone View Post
    It is an electric shift motor and no controls after 1972 had that feature.-----------You would need a control box for -----------HYDRO-ELECTRIC SHIFT -----------with a big round black plug.--No others will work.
    Here's what my shifter looks like!

    http://www.google.com/imgres?um=1&hl...w=1600&bih=775

    Well crap.... that sucks! But than again, maybe not! The one that is on it isn't BAD by any means, it seems to be in working order! (starting the motor, shifting the motor from forward, to reverse, to neutral, etc.) He said when he last looked at it "the throttle cable was just broken". I haven't dug into the remote YET, so I'm not really sure what I'm working with yet! Do you (or anyone!) know if it's possible to just replace the "throttle cable" in the "Hydro electric shift" motors? I'm not even sure what that is? lol... I know that when I throw it into forward or reverse it shifts the motor, battery or not! That's about it so far... ha!

    I just got finished ripping the internals out (seat's mainly). I have her where I want her now though, time to start looking into the motor and controls! (I know I have a little work cut out for me, but it's not bad! And definitely not bad for $150!!)

    Here's how she stands today.... no pics of the motor OR controls though! lol... I was mainly just taking them for friends and family, wasn't thinking about the forum! OOPS!









    Last edited by Chris Herndon; 05-09-2012 at 03:59 PM.

  4. #4
    Join Date
    Sep 2010
    Location
    ontario
    Posts
    9,581

    Default Re: '79 Renken Bowrider (good shape) - "Fishing Boat Project" - *NEED HELP WITH '72 JOHNSON 100HP*

    Motor has to be running in order for it to shift !!!!-----Yes the throttle cable can be replaced.--------Not a good idea to run the motor without the battery in the circuit.

  5. #5

    Default Re: '79 Renken Bowrider (good shape) - "Fishing Boat Project" - *NEED HELP WITH '72 JOHNSON 100HP*

    Quote Originally Posted by racerone View Post
    Motor has to be running in order for it to shift !!!!-----Yes the throttle cable can be replaced.--------Not a good idea to run the motor without the battery in the circuit.
    Oh.... well it may not "shift" but you can look at the motor and see that its doing what it is supposed to! (Atleast by site that is!) I have'nt ran the motor yet and don't plan to until i completely flush ALL the fluids from the oil in the engine to the oil in the lower unit! I've got to get a book for that motor first though!

    Here's another question. How do you replace the THROTTLE cable in the "circuit"...? Is this like an ACTUAL cable?(i.e. brake cable type on a bicycle) Because when I looked, all's I saw was an "electrical" plug and the cable that "shifts" the motor from F-N-R! Or atleast that's all I can see! I'm REALLY confused on this motor! It seemed like it would just be cables and links and stuff.... ARE YOU TELLING ME THEY WERE THIS ADVANCED IN THE EARLY 70'S?! lol...

  6. #6
    Join Date
    Sep 2010
    Location
    ontario
    Posts
    9,581

    Default Re: '79 Renken Bowrider (good shape) - "Fishing Boat Project" - *NEED HELP WITH '72 JOHNSON 100HP*

    The cable that you are looking at is the throttle cable !!-------There is no shift cable as that is done electrically and it SHIFTS ONLY WHEN THE MOTOR IS RUNNING !!-------Yes I agree you need a manual specific to your motor.-------Will prevent you from making expensive mistakes.

  7. #7

    Default Re: '79 Renken Bowrider (good shape) - "Fishing Boat Project" - *NEED HELP WITH '72 JOHNSON 100HP*

    Quote Originally Posted by racerone View Post
    The cable that you are looking at is the throttle cable !!-------There is no shift cable as that is done electrically and it SHIFTS ONLY WHEN THE MOTOR IS RUNNING !!-------Yes I agree you need a manual specific to your motor.-------Will prevent you from making expensive mistakes.
    Well thats actually good to know! That means that the throttle is INDEED working then! I'm not sure what the guy was talking about than! Anyways, I need to get all of her fluids changed out, everything lubed up real good and my battery put in there.... I'm sure it'll be much easier to troubleshoot then!!! Thanks for your help, you've given me hope on a "budget build"!!!

    You, or anyone for that matter, wouldn't know an easy way to explain the changing of the gear oil in the lower unit would ya? Or the changing of the oil in the motor itself? Are the plugs hard to get to? And what type of oil should I use for all applications? I will be doing the compression check, spark check and carb cleaning tomorrow as well, as its supposed to not rain ALL DAY AGAIN! I'm also going to try and "clean up" underneath the motor cover as well.... look for loose grounds, fix any severed wires I see (though all of this looks ok!)
    Last edited by Chris Herndon; 05-09-2012 at 10:54 PM.

  8. #8
    Join Date
    Sep 2010
    Location
    ontario
    Posts
    9,581

    Default Re: '79 Renken Bowrider (good shape) - "Fishing Boat Project" - *NEED HELP WITH '72 JOHNSON 100HP*

    I suggest you get the manual and read it carefully.---------------It is a 2 stroke motor and there is no oil to change on the motor itself.---------Oil is mixed with the gas.------There is a special oil to use in the gearbox itself.---Like I said don't open your tool box untill you read ( understand the basics ) on this motor !!!

  9. #9
    Join Date
    Feb 2001
    Location
    Central West Florida
    Posts
    11,699

    Default Re: '79 Renken Bowrider (good shape) - "Fishing Boat Project" - *NEED HELP WITH '72 JOHNSON 100HP*

    Disregard my replies to your private messages. Your original message contained so much information that I somehow became confused between your 140hp and your latest project. What I had to say in reply was in error and would be misleading.

    Main error pertained to your question about using the later model controls.... No, you must stick to the setup which pertains to the Hydro Electric Shift that incorporates the "black" electric plug at the engine.
    Our questions require answers. If you refuse to answer our questions, how can we answer yours?

  10. #10
    Join Date
    Dec 2009
    Location
    Pickering and Lakefield, Ontario, Canada
    Posts
    593

    Default Re: '79 Renken Bowrider (good shape) - "Fishing Boat Project" - *NEED HELP WITH '72 JOHNSON 100HP*

    Just a thought here, but do the 1972 100hp and 50hp hydro shifts use different electric connectors? My 72 50hp has yellow plug ends??

  11. #11
    Join Date
    Sep 2010
    Location
    ontario
    Posts
    9,581

    Default Re: '79 Renken Bowrider (good shape) - "Fishing Boat Project" - *NEED HELP WITH '72 JOHNSON 100HP*

    The black plug is for the battery electronic ignition systems and yellow plug is for the electronic magneto systems.--------------ONLY the 71 / 72- 50 HP and the 72-- 65 HP used the yellow plugs !!!!-----Just the way it is.

  12. #12

    Default Re: '79 Renken Bowrider (good shape) - "Fishing Boat Project" - *NEED HELP WITH '72 JOHNSON 100HP*

    Quote Originally Posted by joereeves View Post
    Disregard my replies to your private messages. Your original message contained so much information that I somehow became confused between your 140hp and your latest project. What I had to say in reply was in error and would be misleading.

    Main error pertained to your question about using the later model controls.... No, you must stick to the setup which pertains to the Hydro Electric Shift that incorporates the "black" electric plug at the engine.
    Quote Originally Posted by racerone View Post
    The black plug is for the battery electronic ignition systems and yellow plug is for the electronic magneto systems.--------------ONLY the 71 / 72- 50 HP and the 72-- 65 HP used the yellow plugs !!!!-----Just the way it is.
    Thanks for the replies Joe.... (and all!) I understand what you're saying. But since you had the motors confused; should I still test for 100 psi compression and the 1/4 jump on the spark plugs? I'm pretty knowledgeable when it comes to motors in themselves, but just not used to having something that's cooled by water intake (from an unattached source), etc.

    That was MY MISTAKE on the question about the engine oil! Guess I had a goof moment! I disregarded the fact that this is INDEED a 2 stroke and not a 4, like the scooters and go karts I've been working on lately are! Nonetheless, can you give me a good oil ratio for this particular motor (the '72 100hp Johnson)? I'm not sure if I should run her a little rich since she's been sitting for a while... ya know?

    I plan to rebuild the carb. while I'm changing the lower unit's fluids, within the next week or so!(which shouldn't be too hard with the book to the motor and a rebuild kit) Know where to get the best one, kit that is? My dad (who has worked on quite a few boat motors to knows a LITTLE SOMETHING) showed me where to drain and also FILL the lower units gear oil -I plan to use whatever the Evinrude/Johnson dealer (or a GOOD local boat mechanic) tells me to use! I will also be pumping her with grease in all of her "joints" as she seems a bit stiff here and there! (turning, raising and lowering the motor (by hand - another thing I DO NOT LIKE and will be fixed EVENTUALLY!), etc)

    I do have TWO more quick questions, that should be answered with ease from anyone knowledgeable about this motor!

    1. I purchased a Teleflex cable that is a PERFECT length for my boat today off of craigslist! It was a steal at $20 and being BARELY used, as the previous owner went with hydraulics almost immediately after purchasing his boat NEW... Nonetheless, I was "wiring it up" and everything went very smooth from the steering wheel (minus that I need to purchase a few longer bolts AND a different steering wheel - which I already found for ANOTHER steal!!) until I got to the MOTOR mounting part! Obviously this motor doesn't come with the correct mounting hardware for a cable installation, as it came hooked up with a SCREWED UP (from age) pulley system which I RIPPED OUT - that was actually usable in the PAST sometime I'm sure! Haha... Anyways I'm wondering if I can get a buddy of mine to hook me up with a couple pieces of FABRICATED angle iron or something and make me a DIY "Steering Attachment Kit" (as Teleflex would call it). I'm kind of working on a LITTLE budget here and would like to save money wherever possible. If I can get him to fab up the pieces that will mount to the transom and have holes for the mounting portion of the steering cable assembly than that's a free gig! Teleflex's price just seems a BIT to steep for me, especially for something that looks easily mock-able when you have a friend in the metal fabrication business! The piece that hooks to the motor itself (for lack of better terminology) is there, and it will rig up perfectly if I mount the cable end on the transom! Any comments?

    2. The "Hydro-Shift" thing.... this just seems like it's going to be a failure from the get go, as this seems to be the reason the guy ditched the boat in the first place and went and grabbed a shiny new one! So I'm bracing for it ahead of time! Is it POSSIBLE to fix the SHIFTING portion of the cable (the electronic part) without having to buy the ENTIRE control box!? (I did read your write-up Joe, on the 3 way switch thing - not comfortable with it! No offense whatsoever, I'll just have family using the boat and things of that nature!) Or will this whole unit just have to be replaced? No solenoid or fuse or anything that can be replaced instead of the whole "unit"? If not, guess it won't hurt to replace the entire thing - due to its age!

    Thanks for the replies yall, I'm starting to dig into her now! I want to get it STEERING correctly FIRST though and have that in order before "rebuilding" the motor (to whatever extent needed)! So any info on that and my "plan" would be great! Thanks everybody, special thanks to Joe up there!
    Last edited by Chris Herndon; 05-12-2012 at 12:34 AM.

  13. #13
    Join Date
    Feb 2001
    Location
    Central West Florida
    Posts
    11,699

    Default Re: '79 Renken Bowrider (good shape) - "Fishing Boat Project" - *NEED HELP WITH '72 JOHNSON 100HP*

    Thru the years, I've lost track of the color codes pertaining to the main electrical plug setup at the engines (Black, Yellow, Red, whatever). The important thing is that the colors cannot be mixed.

    The following paragraph applies only if all wiring, shift switch, etc is as it should be.

    Testing shift w/o engine running.... Remove s/plugs and ground all plug wires. Have key in ON position. Put unit in whatever shift mode desired. Bypass safety switch and crank engine by using small jumper from battery terminal of starter solenoid to the 3/8" nut terminal of the solenoid that engages the starter circuit (not the 3/8" ground nut!). The unit should shift into the proper shift mode within 3 or 4 revolutions.

    Shifting can also be checked by having the proper voltage applied, or not applied, directly to the wires leading to the lower unit at the engine location. Wires must be disconnected from the engine harness. Forward=no voltage - - Neutral=12v to Green wire - - Reverse=12v to both Green & Blue wire.

    Mixture is 50/1... 1pt of good quality 50/1 oil to 6gal gas. 87 octane will be fine.

    Gearlube drain is a large screw with regular screwdriver slot in bottom of lower unit. Oil level is identical screw further up the lower unit. Of course remove both screws to drain. Fill from bottom until gearlube flows out oil level hole, insert top oil level screw to create an air pocket. Remove oil fill device and insert drain plug as quickly as possible.

    Gearlube must be "Premium Blend", also known as "Type C", available at your dealership, possibly Sierra and this site. If it's available elsewhere, I'm not aware of it.

    You CANNOT use the "HiVis" 80/90w gearlube that is used in standard mechanical shift models!
    Last edited by joereeves; 05-12-2012 at 09:21 AM.
    Our questions require answers. If you refuse to answer our questions, how can we answer yours?

  14. #14

    Question Re: '79 Renken Bowrider (good shape) - "Fishing Boat Project" - *NEED HELP WITH '72 JOHNSON 100HP*

    Quote Originally Posted by joereeves View Post
    Thru the years, I've lost track of the color codes pertaining to the main electrical plug setup at the engines (Black, Yellow, Red, whatever). The important thing is that the colors cannot be mixed.

    The following paragraph applies only if all wiring, shift switch, etc is as it should be.

    Testing shift w/o engine running.... Remove s/plugs and ground all plug wires. Have key in ON position. Put unit in whatever shift mode desired. Bypass safety switch and crank engine by using small jumper from battery terminal of starter solenoid to the 3/8" nut terminal of the solenoid that engages the starter circuit (not the 3/8" ground nut!). The unit should shift into the proper shift mode within 3 or 4 revolutions.

    Shifting can also be checked by having the proper voltage applied, or not applied, directly to the wires leading to the lower unit at the engine location. Wires must be disconnected from the engine harness. Forward=no voltage - - Neutral=12v to Green wire - - Reverse=12v to both Green & Blue wire.

    Mixture is 50/1... 1pt of good quality 50/1 oil to 6gal gas. 87 octane will be fine.

    Gearlube drain is a large screw with regular screwdriver slot in bottom of lower unit. Oil level is identical screw further up the lower unit. Of course remove both screws to drain. Fill from bottom until gearlube flows out oil level hole, insert top oil level screw to create an air pocket. Remove oil fill device and insert drain plug as quickly as possible.

    Gearlube must be "Premium Blend", also known as "Type C", available at your dealership, possibly Sierra and this site. If it's available elsewhere, I'm not aware of it.

    You CANNOT use the "HiVis" 80/90w gearlube that is used in standard mechanical shift models!
    AGAIN! Thanks for the reply and helpful advice Joe!!! I've kind of "given up" on the motor (I have IT, along with the entire boat AND motor up for sale right now!), as I had ANOTHER boat traded to me for an old non-runnin truck! It's a 15ft Rally, weighs almost DOUBLE what the 17ft Renken does (probably due to the Renken's open bow and the Rally's "Walkabout" style!). Nonetheless, we took it out in about 5 ft. "seas" (Chesapeake Bay) yesterday and it took it LIKE A CHAMPION! This boat is VERY solid and takes big rolling waves and such with EASE! Even at full throttle, never a bog down and never a break in speed!

    It has a 1968 55hp Evinrude Triumph on it.... the motor runs GOOD, REAL GOOD (as previously mentioned)! The ONLY drawback I have from the motor is it's torque... it has NONE! From an idle "roll", if you FLOOR IT, it takes about 20-30 seconds to catch up and give it's full potential (and honestly I don't think the motor is giving me all she's got anyways, as top end is NOT THAT FAST - maybe I'm expecting too much out of a small motor?? But the boat is ONLY 15ft!!)! I believe the prop may be TOO BIG or have too much or too little "pitch", and that's my problem! The guy I bought it from said the OLD prop he had on it was torn to HELL, so his buddy gave him one of a 100 Evinrude of AROUND the same year. It idles PERFECTLY, just a nice, low "purr" - but she WILL stall SOMETIMES! THAT BEING SAID, when she's put into gear (even with the low idle) it seems as it's ready TO GO! Makes for hard docking when you have to push buttons for forward and reverse, PLUS she's wanting to race around at idle speed! I'm REALLY THINKING prop! What is a good prop for this motor?

    I want good TOP END of course, due to it's "speedy" looks and low profile but I want to be able to GUN IT and it SCREAM getting there! (for skiing and wakeboarding) I've noticed on the motor that it has the "throttle body cover" missing, could this make a difference? I know the motors DO NOT have actual filters for the intake, but could the box that is supposed to go over top of it make THAT BIG of a difference? (where could I find that part?) Also when you choke it on the motor and turn it the FIRST time, you get some fuel leaking out the throttle "flaps".... it fires, than the choke is cut off and it runs fine (no more fuel seen)... is this normal for a 2 stroke? Or is it running hella rich?! I've got the fuel mixture dead on, doesn't smoke but a TAD!

    If ANYONE could help on this 55hp now, it would be appreciated... as this is the NEW and IMPROVED project boat!!!

Similar Threads

  1. Merc 496 "overheat warning" sounds before boat is even started
    By aafattore in forum Mercruiser Sterndrive Forum
    Replies: 52
    Last Post: 09-27-2011, 05:27 PM
  2. Design Feature "V" - "Special Gearcase" - What does this mean? J150VXSIG
    By weirdaljr in forum Johnson Evinrude Outboard Forum
    Replies: 4
    Last Post: 05-14-2011, 08:59 AM
  3. Replies: 3
    Last Post: 02-22-2011, 11:31 AM
  4. Replies: 4
    Last Post: 01-19-2011, 03:28 PM
  5. I gotta good one...."turning over engine"
    By Jettywolf in forum Honda Outboard Forum
    Replies: 3
    Last Post: 10-21-2010, 11:03 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •