Why won't my 'Rude start?

[chdabren]

Hey all! I have a '74 'Rude 85 hp (85493B) that has 115 psi. compression in all 4 cylinders (which I assume is good). It IS a 2 stroke. Here's my dilemma...I can't get 'er to run on her own w/out dumping gas directly into the cylinders and letting the vacuum fill up the carbs.. Yes, I'm trying to ready it for spring. Already did an impeller and what not. I'm getting fuel to the pump. After basically flooding the cylinders with fuel/oil mix and cranking it over (this takes approx. 1/2 hour to get going), it finally catches and runs on it's own. I don't understand why it does this. Could it be that the carbs are all gunked up and need rebuilding? Do these carbs have float bowls that are difficult to fill? Am I missing something here? Is there a "trick" I need to know about? Once I've got it running on it's own...she runs good, altho my "push to choke" solenoid doesn't work and I'm not sure why. I'm assuming the compression test (115 psi in all 4 cylinders) is a good sign the motor is still in good shape. Also, on my exhaust housing, I have 2 holes just under the engine and I just noticed that I get water spray out of them when the engine is running. I'm assuming it's from the water pump pumping water up to the motor. I never noticed water coming from those 2 holes before and I'm wondering did I do something wrong? I have it shooting out the tell tale nozzle at the engine. Anyway, if anyone has a tip or idea that can help me out, please share. Thank you.

 

[freddyray21]

Re: Why won't my 'Rude start?

water out of those holes is normal. As for not getting it to start it sounds like a fuel issue to do with the choke if it runs fine after you get it started. Try manually choking it. There should be three positions on the choke lever. On, off and auto. In order for the electric choke to work it needs to be in the auto position. You should still be able to manually choke it though.

 

[jtexas]

Re: Why won't my 'Rude start?

You have to choke it for a cold start.

I believe it's just two positions for the manual lever on that motor, open or closed - when it's open, the solenoid can close 'em.

take the airbox cover off, you can see whether the choke plates are closed off all the way.

cold start procedure:
Fuel line pressurized, hi-idle lever full up, chokes closed, turn key to "start" until it starts, (shouldn't take more than 3 or 4 seconds) release key/open chokes immediately, back off the hi-idle - give it just enough to keep running. If it starts to die, bumping the choke for just an instant usually keeps it going.

How long since you last had it out? carbs might need rebuilding but generally that won't keep it from starting.

 

[billybones]

Re: Why won't my 'Rude start?

is the fuel prime bulb good and hard before you try and start it? this is what fills your bowls before you start it. I assume this is an outboard. If I am wrong ignore me.

 

[tashasdaddy]

Re: Why won't my 'Rude start?

when was the last time it ran normally? was it winterized and fogged? seafoam added to the fuel, and ran thru the motor? either fix the choke or use it manually

 

[chdabren]

Re: Why won't my 'Rude start?

The last time this engine was run for any length of time (since it hasn't seen any "action" in about 2 yrs) was last year just to keep the blood flowing so to speak. It's never been fogged to my knowledge. But it didn't have a problem starting last year at all. As I said, it's got 115 lbs. compression in each cylinder, which I presume is good. It runs strong, no doubt about it but is just hard to get started on it's own. I have to manually put fuel into the cylinders multiple times to get it to run and eventually it does take off on it's own. The choke solenoid isn't working for w/e reason. I have power at the solenoid but the solenoid doesn't actuate. I'm wondering if, when I tested it by touching the terminals to 12 volts (albeit briefly), I burned it out. Anyway, if anyone has more info they can share, I'd be grateful. Thanks

Chris

 

[crb478]

Re: Why won't my 'Rude start?

How strong is your battery, and are your battery cables in good shape? It needs to turn over at 300 rpm to crank and the choke plates need to be fully closed to suck fuel into the cylinders. If it will not start with full choke and a good battery you may need to rebuild the carbs. If it runs good otherwise you may have a valve seat sticking and not allowing fuel in bowl.

 

[jtexas]

Re: Why won't my 'Rude start?

touching the solenoid terminals to 12 volts is the equivalent of closing the switch - that didn't hurt it. Did you jump both the positive and negative? If so then you know the solenoid's faulty, otherwise you still don't know if it's a bad connection or wiring fault on the ground side. A little troubleshooting with a voltmeter will tell you that.

Have you tried to choke it manually?
Does the fuel line hold pressure?

 

[chdabren]

Re: Why won't my 'Rude start?

Battery is new and fully charged, cables are new as are terminals. I have plenty of crank power and I can tell you this thing turns over at more than 300 rpm. When I pump up the fuel, not only does the bulb remain solid but I know I'm getting fuel into the carbs. I took off the fuel line below the air box and squeezed the bulb and plenty of fuel is getting in. I have attached my multimeter to the choke solenoid and used my "push to choke" and I have power at the choke. This is why I wonder if the solenoid is burned out. I've mention the compression test results many times now and no one has indicated if the results are good. They were 115 psi. per cylinder x4. I've been told this is excellent for a V-4. I really wish I had fogged the motor but I guess I didn't realize the importance of it. But dam, the motor runs strong once it's going!! Does the position of the motor have anything to do with the float bowls filling up? I haven't had it exactly straight up and down but not at full tilt either. Anyway, you guys have been awesome with advise and you've no idea how helpful it's been. I'm a master automotive tech, not a boat tech but the basics always apply, whether 2 or 4 stroke. This is a 2 stroke so there won't be any "valves" in the engine, that I know of...lol. I'll try the suggestions everyone has made so far and let you know what I find out. Thanks again.

chris

 

[chdabren]

Re: Why won't my 'Rude start?

P.S....yes I've choked it manually and have the same results. But that may be because I don't have the lever on the other side on the correct setting. I'll try again.

 

[jtexas]

Re: Why won't my 'Rude start?

115 on all four is very good for a '74.

Nah, the tilt doesn't affect it - if you tilted full up, gas would drain only if the float valves leak.

These carbs are incredibly simple compared to automotive - just a couple fixed jets. You'll probably end up rebuilding 'em, it's not such a bad chore.

Apart from choking, the other main thing that affects cold starting is the spark advance - when you move the hi-idle lever to the start position (full up), make sure the timer base is advancing all the way to its stop.

And fuel quality - if the gas is more than a few months old, it'll need to be drained & replaced, unless maybe you added stabilizer.

Highly recommend a service manual - your OEM manual is available at kencook.com or marineengine.com - well worth the price.

 

[chdabren]

Re: Why won't my 'Rude start?

Hi everyone! After some looking around and taking the carbs off, I did find a few things that are probably causing problems. Things you can't see unless you DO take the carbs off. I found a couple fuel hoses dry rotted (altho not leaking) that are sucking small amounts of air into the carbs. I found the carb mount gaskets aren't sealing properly. The carbs themselves look very clean, no signs of dirty or anything else. The throats are shiny and pit free, blades move completely freely. This engine amazes me!!! Now I know why my father and grandfather swear by these older Rudes. For all I know this engine may have done alot of sitting around. When I pulled off the carbs I looked into the lower part of the block where the air/fuel mixture comes thru and it's absolutely spotless. I can actually still see the molding process inside the block as tho it just came off the assembly line. This engine is 34 yrs old and clean!!! Looks like I'm just gonna need to replace those rotted hoses, clamps, gaskets, etc...and probably some fresh plugs and be good to go!! Cautious optimism. . Anyway, I'll repost after I've done this work and let you all know how it turned out. Gonna empty a couple cans of carb cleaner thru them too. Thanks again everyone!!

 

[crb478]

Re: Why won't my 'Rude start?

You probably have found your problem. Air leaks will play havoc with getting one to start. Its a good idea to replace teh lines just from a safety stand point.

 

[billybones]

Re: Why won't my 'Rude start?

rebuild the carbs. Unlike a car they need to be cleaned. not just soaked with spray cleaner. because of the amount of oil in the fuel the gunk up. You have them off just do it. It's not like you would put a used strainer on an electric fuel pump. This is about the same... happy boating.

 

[chdabren]

Re: Why won't my 'Rude start?

ok....so an update on what I've done/found so far. I replaced the rotted fuel hoses and pump up the bulb on the fuel line. It got hard but I distinctly heard a whistling type noise within the fuel pump and the bulb went soft within 10 seconds. So I disected the fuel pump and found that the inlet check valve is allowing fuel into the pump but the outlet side check valve chamber (the side that feeds fuel to the carbs) was dry. No sign of fuel getting thru it. The way I see it, the internal diaphragm isn't working properly, hence isn't allowing fuel into the outlet side to feed the carbs. The diaphragm looks rough. Using common sense, I believe the outlet side check valve chamber should be just as wet from fuel as the inlet side. Am I correct? The pump definately isn't holding pressure. I'm hearing a distinct whistling sound with every pump of the bulb. I took off the hose that connects to the "feed" side of the pump which runs to the carbs. I can pump the bulb up with that hose still connected and I found that fuel just drains right back out. I'm assuming it should hold pressure (?). Anyway, that's where I'm at with it now. I think if I do a new fuel pump, I should solve my fuel problem. My next question however is this....I have 3 connections on my fuel pump. One is feed from the tank that goes to the filter, the 2nd is feed from the pump to the carbs., the 3rd one appears to have a vacuum hose connected to it that runs to the block. What is THAT line for? Is that where my vacuum source comes from for the engine vacuum to continue sucking fuel in? Sorry to be such a pain...just wanna get this engine running on it's own. Thanks for the help

Chris

 

[jbjennings]

Re: Why won't my 'Rude start?

Yes, the 3rd line is for pulse vacuum off the block. You're wise for rebuilding it. A carb cleaning does sound in order but fixing the vacuum leaks and fuel hoses may definitely do the trick.
JBJ