oil and gas question 58 7.5 sea horse

[fishingkid]

I have a 58 sea horse 7.5 on a 12' aluminum boat. My question (something that the repair manual doesn't explain) is there are two knobs on the front of the motor one for high speed and one for low speed (richness and leaness) I set the low one for the best throtle response (around 3 1/2) but was wondering how I am really suppose to set them. I was also told to mix the oil with atleast a 25:1 so I did a 24:1 shold that be close enough?with a synthetic 2 stroke boat motor oil I got at walmart. Should this be okay? Sorry it is so long and thanks in advance, James

 

[JB]

Re: oil and gas question 58 7.5 sea horse

Ahoy, Fishingkid.<br /><br />You have the correct fuel/oil mix. 24:1<br /><br />The low speed jet is adjusted for a smooth idle. 3-1/2 sounds reasonable.<br /><br />The high speed jet is set for WOT operation. Back her out until the engine "four strokes", or burbles. Then turn her in until she smooths out at max rpm.<br /><br />Good luck.

 

[fishingkid]

Re: oil and gas question 58 7.5 sea horse

alright thanks JB I thought I wanted to make sure it wasn't pinging and that it ran smooth so I guess I am alright there but I just wanted to make sure that I am not harming it. Also there is a little oil in the bucket that I was running it in after about 5-10 minutes (maybe 6 half dollar sized pools on the surface is this normal for this era 2 stroke (I know when my old YZ 250 did that I changed the jetting and it stopped spittting all the oil out the exhaust. Just thought I'd ask. Thanks James

 

[JB]

Re: oil and gas question 58 7.5 sea horse

It is normal for unburned fuel/oil to show up in the tank, Fishingkid.<br /><br />You are doing just fine.

 

[fishingkid]

Re: oil and gas question 58 7.5 sea horse

Thanks agian hopefully I will get out tonight for the trial run. Thanks again James

 

[fishingkid]

Re: oil and gas question 58 7.5 sea horse

JB or anyone ho is familiar with these older engines. I ran it in the test buket for about 5 minutes and was just thinking about it. Where should the water come out (from the shaft above the water line or below?) I was thinking that it was the one below, but am now thinking that I may be wrong and that, that may be the exhaust(book says the hole above the prop for water but there is two). If this is correct how hard is it to change the water pump? I am going to look at the book but I am just thinking. Thanks James

 

[fishingkid]

Re: oil and gas question 58 7.5 sea horse

anyone know which hole it is suppose to come outta the one dirrectly above the prop or the on on the shat above the water line? Thanks James

 

[Fouled Plug]

Re: oil and gas question 58 7.5 sea horse

Both, actually. You should see a healthy spray of water out of the exhaust port above the waterline. The impeller change isn't a major chore, and is easily accomplished with basic tools (and a manual) If you don't know when it was last changed, do it. Cheap insurance!

 

[fishingkid]

Re: oil and gas question 58 7.5 sea horse

Fouled plug thanks I am replacing it but the water pump appears to be in good shape (all there)snug fit in the housing etc. (but then again I don't know how they are suppose to go bad so maybe it is anyway to tell really??) The last time I ran it there was no water comming out the one in the shaft above the water line but the water in the buket was flying all over so I don't know if it should be comming out there it appeared that that was the exhaust not a water outlet though. Thanks again James

 

[Paul Moir]

Re: oil and gas question 58 7.5 sea horse

I wouldn't consider the test to be meaningful unless the water level was at least up to where the base of the water pump is when tested. It sounds to me like you had it in a real small bucket, and the water pump was mostly sucking up air.<br />So, I'd test it again in a larger bucket like a garbage can, filled to the water pump, and see if it works then.<br />Good luck!<br /><br />EDIT: The vanes of the water pump should be turned over a bit. When you put the impeller into the housing turn it clockwise from the top, or counter clockwise looking at the bottom of the housing.

 

[fishingkid]

Re: oil and gas question 58 7.5 sea horse

Okay thanks Paul but there is one problem currently. I already took it apart. So I really cant do that just yet. One thing though I put water into the port that water is pumped through and thre a little compressed air through it and there was a bad soft plug in the head (the little tinny ones about the size of a pinkie). So I will have to replace that. My next ?'s are the motor doesn't sit in the water down to the pump (it is higher than the plate above the prop, about mid shaft) so is it forced in basically while in motion or siphoned in by the impeller? And if the star is tight against the walls is it deffintally a good pump? One of the two I have I had to get wet for it to let me spin the driveshaft going through the pump should this be a good one???? Thanks in advance James