1988 Johnson Seahorse 4hp advice please

[yamzy]

bought a johnson engine today model bj4brccs, which i figured out is a belgium johnson 1988 engine.

just a couple of things i would like some info on if you would be so kind please.
its all working good but i would like to give it a look over and replace a few things my self.

so the plugs, they are b6hs ones(very rusted). i had a few brand new br6hs plugs lyin about and i've put them in runs fine etc will these be ok or should i buy new b6hs ones.

fuel mix. i was told it can be 100:1 or 50:1 whats best for its health.

it sprays misty water out of some holes in the shaft, but i really would like to check the impellor as i think the engines been unused/unserviced for a while.
how would i check the impellors condition thanks.

 

[oldcatamount]

Re: 1988 Johnson Seahorse 4hp advice please

Changing the plugs is the easiest and one of the best things you can do for your motor. Use the 50:1 mixture for your fuel. The impeller is a little more involved as you need to drop the lower unit to get at it. Don't be afraid to try the job by yourself. No special tools are required and it's a straight forward repair. When you buy the new impeller, get the "repair kit". It'll have everthing you need for the job.

 

[Rick.]

Re: 1988 Johnson Seahorse 4hp advice please

Does you motor have forward and neutral? I would suggest Champion plugs and changing the gear oil too. It won't take much gear oil but then you 'll see if your getting any water in there. Your plugs are rusted. On the electrode side or the wire side? Best of luck. Rick.

 

[yamzy]

Re: 1988 Johnson Seahorse 4hp advice please

cool so are the new br6hs plugs i used to replace the b6hs's fine, or should i get 2 new b6hs plugs.

50:1 thanks i thought that myself but wasnt sure, and if nothing can go wrong i'll ave a bash at the impellor myself.

theres 1 more thing i forgot, while i had the cowel off i noticed a big long upside down T shaped screw that connects to the tank, is this just a fuel shut off or some mix ratio thing i may of twisted it a few times.

i noticed it already has a fuel on/off switch on the front does this model have 2 ways to shut off fuel ?

 

[yamzy]

Re: 1988 Johnson Seahorse 4hp advice please

Does you motor have forward and neutral? I would suggest Champion plugs and changing the gear oil too. It won't take much gear oil but then you 'll see if your getting any water in there. Your plugs are rusted. On the electrode side or the wire side? Best of luck. Rick.

plugs wer rusted on the outside, the hexagons which you tighten the plug with. they worked fine tho the nipples and inside electrode where good.

yes it has forward and netral too works fine, i have some gear oil which i used for a seagull. will this be ok to use i forgotten what type it is, what type of gear oil is best for this johnson

 

[Vic.S]

Re: 1988 Johnson Seahorse 4hp advice please

I think your engine has points ignition. If so the BRHS6 will be fine. They are the same as BHS6 but with resistive suppression ( BRHS6-10 and BHS6-10 also Ok but the -10 indicates that they are supplied with a 1mm gap so would have to be closed to 0.7 to 0.8 mm)

OMC CD ignition requires inductively suppressed plugs if suppressed plugs are used and BZ7HS-10 would be the NGK plugs to use.

A little confused however about what type of plugs are correct. The lists show Champion QL86C or L86C for earlier models ( B6HS would be suitable ) but QL77JC4 for the 1988 model, the equivalent of which would be the grade 7 NGK plugs

Id certainly start by determining if it has points ignition or electronic ignition You'll recognise the latter by the power pack and coil assemblies whereas points ignition has coils out of sight within the flywheel

50:1 is the correct fuel mix for your engine. OMC tried 100:1 for a couple of years or so starting in 1985 but soon discovered it was a mistake!

Seagulls mostly used a grade 140 gear oil. Your Johnson requires an outboard engine gear oil with a viscosity of around 80W90

Cannot answer you question about the upside "T" shaped screw. Your particular model is not shown on the BRP parts diagrams .. that often happens with Belgian models that were made for the European market. If it has the fuel hose connected to it assume it is a fuel tap and figure out how it works. Otherwise not!

 

[yamzy]

Re: 1988 Johnson Seahorse 4hp advice please

just had the cowel off , only thing i can see ignition wise is the HT wires.
theres no cdi, powerpack or coils in sight. also it has no kill switch

I would say you are correct about points system. I've looked at the J4rccs parts list myself and was told this is most similar to my model. but i can see quite a few differences.

anyhow to the point if it is points then br6hs's are good yes and about the gear oil i'll post a link and would appreciate if you could tell me if this is the right stuff for it.

http://cgi.ebay.co.uk/Gear-Oil-API-...arts_Vehicles_CarParts_SM&hash=item255deaabcf

cheers and 1 more thing! im guna get the lower unit off tomorrow and inspect the water pump/impellor.

if its all in good condition will it be ok to just put back together? or will i need new seals or anything thanks.

 

[Vic.S]

Re: 1988 Johnson Seahorse 4hp advice please

Yes with points ignition, which you seem to have, the BR6HS plugs will be OK.

The oil is the correct grade, (SAE 80W90 GL5) but it is for cars. It does not contain the extra corrosion ihibitors that an outboard engine gear oil does.
(Ive been using it for years but I dont normally admit to it)

I would not put an old impeller back in after going to all the trouble of getting it out. I'd put a new one in.

While the gear case is off its a good time to consider new seals. At least the drive shaft seal under the water pump.

Do I figure correctly that you are in the UK ?

If so two good sources of spares are www.willsmarine.co.uk in Kingsbridge Devon and www.outboards-direct.co.uk (Oakley Marine) in Brighton. Quote your actual model number when ordering spares.

Good general forums for boating advice etc in the UK www.YBW.com/forums

 

[yamzy]

Re: 1988 Johnson Seahorse 4hp advice please

so i guess it will run good with that oil then but its not ideal.

you probably right pointless to take it apart without renewing a few things, I am in the UK and i've just emailed those sites about a new impellor and seal so i just need to wait and see what they say now.

hopefully thats everything serious covered now. cheers for ya help matey, finding info on this engine is a pain. i've even got my self a 71-89 manual for it online which gave little help, well it might come in handy for the lower end

 

[Rick.]

Re: 1988 Johnson Seahorse 4hp advice please

http://epc.brp.com/Index.aspx?lang=E&s1=c4c4e88b-91bc-440c-a80f-12eb0275c196

I'm not sure if your aware of this site. It will give you a good concept of how everything goes together as well as the specific parts. Your right to change the impeller. The general rule of thumb is every 2 to 3 years it should be replaced and when you first purchase the motor if you have no idea when it was last done. Hope you have success at getting the parts you need. Rick.

 

[yamzy]

Re: 1988 Johnson Seahorse 4hp advice please

yes rick i am going to definately replace the impeller, i had it running the other day too in a tank, its spraying water but not that much also it got very warm only just touchable.

I've been on that parts site several times, unfortunately i can only find some similar looking models but mine isnt on there bj4brccs.

I emailed a few sites which vic mentioned asking if they stocked the impeller for my engine but still waiting for a reply it would be helpful if somebody could help me find the part number for the impeller or a suitable one.

would like to get it bought and fitted asap so i can get her out for spin. but so far i cant figure out which impeller i need.

 

[dazk14]

Re: 1988 Johnson Seahorse 4hp advice please

sounds like it's time to post some pics of your motor...

 

[yamzy]

Re: 1988 Johnson Seahorse 4hp advice please

tell me about it mate, nothing is simple with me.

i bought a seagull a few months back cdi went on it. turned out it was really rare and was guna cost best part of ?100 to fix so scraped it.

now i've bought a johnson which seems to have no information on any websites about it or in the manual i bought.

thankgod theres sites like this tho with people who are willing to offer help, if not id be stumped and probably run it how i bought it and have it cease or blow up.

so yes i'll take the lower unit off tomorrow and get a few pics, you cant beat seeing with your own eyes i guess.

 

[Vic.S]

Re: 1988 Johnson Seahorse 4hp advice please

Surprised you have not had a response from Oakley. Last time I emailed them I had a phone call back within a couple of hours. ( Part took a week to get from Belgium but at least the initial response from Oakley was 1st class)

My guess is that the impeller is the same as for the J4RCCS and J4RHCCS, 0396852.

They were the same part for 1987 and several following years. Earlier ones had more vanes but otherwise I think are the same.

You have not really scrapped a Seagull have you ?

 

[Rick.]

Re: 1988 Johnson Seahorse 4hp advice please

yamzy. You have to be careful what you say around Vic. LOL Rick.

 

[yamzy]

Re: 1988 Johnson Seahorse 4hp advice please

i've just checked my mail and have a response from wills marine, 14 quid for the impeller and they have it in stock. Awesome that should be that.

as far as the seagull, i paid 85 quid for it off ebay. was told it worked and it did i got a whole half a mile before the cdi went. it was a white rare one or something

wasnt willing to spend more then i paid for the engine again just for a cdi. i never scrapped it, but i did sell it off as spares on ebay part by part sadly.

i even got 15 quid for the duff CDi from john at saving old seagull's i guess they are hard to come by and still worth cash even when broken

 

[yamzy]

Re: 1988 Johnson Seahorse 4hp advice please

i've now sourced the impeller i presume 0396852 part was right even tho i dont know the part number of the new one.

i think this because the impeller housing part number was 0329091 which corrisponds to the J4BRHCCS. so will remeber that model for future reference.

Just had the lower unit off pretty simple really. impeller veins are quite worn, drive shaft had a bit of rust on it too but sanded all down.

also the oil was nice and black couldn't see a hint of white in there, so a good sign right.

1 more question tho, the water pipe looks like its copper and has a fair amount of green build up both outside and looks like its inside too.

whats a good way to give it a good scrubbing inside, i can't think of anything i have in the house to do it so may have to purchase something

 

[raczekp1]

Re: 1988 Johnson Seahorse 4hp advice please

hi.
puting back shift rod be careful,there is small hole in lower unit, that shift rod has to go in this hole, otherwise if you will not fit in this hole so there you will have only forward gear and NO neutral and gearcase oil will float out from lower unit housing.
doing reasemble job be careful

 

[Vic.S]

Re: 1988 Johnson Seahorse 4hp advice please

The oil should not be black! It should be no more than a bit darker than when new. I reckon it was long overdue for a change. Every year recommended. If it's not "clear and bright" it's a sign of water ingress.

Best bet drain it thoroughly, flush it with some cheap car engine oil and drain it out again. Refill with the correct oil fitting new washers to the drain and vent screws.
Check for signs of water again after its been run a few times.

Lightly smear the drive shaft splines with grease when reassembling, but not on the end, just the splines.

Water tube is copper but I have no suggestion for cleaning it

Note the comments about refitting the shift rod. It goes through an O ring that forms an oil seal so be careful not to damage that.

Turn the flywheel as you push the drive shaft up into position if necessary to get the splines to line up

 

[yamzy]

Re: 1988 Johnson Seahorse 4hp advice please

cheers for ya help all, threads been dead for a while now, but i still havent used this engine yet.

so fars its had new plugs, impellor and seals.

still need to change the gearbox oil. it was black when i had the lower unit off and some seeped out.

im really hoping that even dispite this rubbish weather i can get her out this friday coming, with my dad whose just got a new engine and boat.
i have another Q please.

how much oil does it need i've seen some on ebay high vis outboard gear oil 80w 90 @10ounces which i believe works out at 300ml is this enough.

also dispite the new impellor its pumping about the same amount of water as the old impellor did and gets very hot in the test tank.

actually burnt my fingers ouch!! when i picked it up duh. how hot should they get i noticed the water pipe had copper green build up could this be blocking water flow? well i guess it could. how easy are they to replace cheers.

i really dont want it to seize up, maybe im just been a bit paranoid i'm new to boating really and my previous engines wer duffs cant be bothered with that again.