'70 55hp Chrysler - minimal power - won't idle

[norenebeaver]

Hey all - have been reading your posts and have been able to solve a few problems except for the above.<br /><br />We purchased a 1970 14' SeaSwirl with trailer for $695 - never saw saltwater, original owner - what a deal. The owner had the motor overhauled a year ago but then it sat as he is up in age and just coudn't do it anymore. We emptied the fuel tanks and are running at 50:1 ratio. First trip out she wouldn't fire - dead battery - came home charged it, took her out again she fired sometimes with some coaxing but wouldn't idle - researched the battery a little found it wasn't a starting battery so purchased a starting battery and just use the other for the fish finder and the trolling motor. Also in the mean time pulled the plugs and found they were set differently so set them both at .23 (approximatley) took her back out she fired right up but still wouldn't idle. So when we start up the boat I give her half throttle let her run for 30 seconds or so and then very quickly (& gently) slap her into neutral push the toggle (for lack of the right word) switch in and slap the throttle forward and off we go. We tried to work on her a little bit Monday and played with the screw above the air intake on the carb (?) it worked for a little bit but then I think he over adjusted it and she won't idle again - can you tell me the best way to make sure it's adjusted correctly?<br /><br />Now the power - I would think that on a little 14' with a 55hp she would scoot at least a little - well, she don't LOL. I don't even think we hit 5mph let alone plane out. We have played with the pitch of the motor on the boat a little and it doesn't seem to help - it seems like the motor sits real low in the water - can you tell me how deep the prop should be in the water. It has a 10 3/8 x 11.5 prop on it now - a few posts I have seen talk about increasing the pitch but I cannot seem to find anything that is 10 3/8 and go above 13 - is that really enough to make a difference? I just went out to look at something and I played with the spring loaded switch near the carborator that is controlled by something that resembles a square and compass and it doesn't go all the way forward or down like something is keeping the square and compass piece from letting the spring loaded switch reach it's full potential....please forgive the wording - yes I am female and don't know all the proper nomenclature.<br /><br />How can I check compression at home? How can I tell if both cylinders are sparking?<br /><br />Also - there's no filter on the carb - should there be - it's just a big ole hole?<br /><br />There are no instruments on this thing so no way of knowing what rpm or knots this thing is really going......<br /><br />Oh - and the bulb that we pump on the fuel line doesn't get hard hard - it works but it never gets real hard..........<br /><br />Okay - is that enough questions - LOL.<br /><br />I believe the model # is 55571???<br /><br />Looking forward to your help and reply's.<br /><br />Blessings<br /><br />Norene

 

[stevecarr]

Re: '70 55hp Chrysler - minimal power - won't idle

My 1966 20 hp is doing about the same , I changed the plugs , screwed with the carb , cleaned it as best as I could (spray) , checked the float in the carb bowl , changed the lube in the lower unit , very easy to do , and I still get NO idle , I just crank it and let it run about mid throttle for a minute and then let it idle down as far as it will go and then stick it into gear and give her the gas ! It took a little getting use to , but works ok , I just get close to where I'm going and shut it off and use the trolling motor to finish ! ! I heard of trying a hotter plug , but if at all wrong will do much damage to your motor . I believe my old carb needs rebuilt , the cheapest I've found was $ 140 <br />Then I found a NEW carb for $ 97 bucks on a website that stocks old / new stuff for older motors . Yours may also have the old points / condenser setup , these are always suspect too. I just don't want to put any $$$$ into this old boat and motor ( 1965 / 1966 ) Make sure your water is moving thru the motor also for cooling. <br />I am trying a hydrofoil Saturday to help my planing problem also . <br />Steve ( better bassfisherman than boat fixer )

 

[stevecarr]

Re: '70 55hp Chrysler - minimal power - won't idle

compression checkers at a auto store can be had for around $ 10 . My motor has no filter on the carb or gas line ? I bought a new bulb and hose just to eliminate that from being a problem <br />( $ 11 Wally world )<br />The carb screw with the spring is usually the lean / rich mixture . From what I've read on here , I was told to be running down the lake and adjust it in or out til it runs funny / bad and then go the other way and do the same then stick it in the middle of that range , I did it at home in neutral and someone said it's not the same as when your in gear under load ? So I'm not 100 % on either method , maybe someone can clear that up for both of us !! <br />My boat ran really crappy , like only 1/2 of what I thought it should , so I checked the plugs at home and they were very wet with fuel , changed them and went out the next day , like a new motor . well almost : ) I keep a spare set in my tackle box just in case !! <br />Steve

 

[eurolarva]

Re: '70 55hp Chrysler - minimal power - won't idle

This is what is recommended to do with a motor that is new to you. First get a manual. Click here syloc manual <br />This manual is good because it is geared to the layman that dont know motors. You can buy a compression tester at sears or an autoparts store for about 30 bucks. I would go to NAPA and buy a carb kit NAPA part number 18-7037 (about 15 bucks) and a fuel pump rebuild kit Napa part number 18-7806 (about 10 bucks). Also install new fuel lines and clamps. Then buy L82C champion spark plugs (also at napa 2 bucks each) gapped at .030 inch.<br /><br />These look complicated but it is pretty simple. The carb kit comes with good instructions and the diaphram on the fuel pump kit is the main thing you will need to replace.<br /><br />Compression test is done with a warm engine. Remove both spark plugs. Screw in compression tester to one of the cylinders and crank a couple of times. YOu need to make sure the plugs are attached to the plug wires and the tips of the spark plugs are grounded to the motor. You also need to make sure the lower unit is in water or you have water muffs attached to the motor. <br /><br />There is a long list of things that should be done but the first thing I would do is compression test and new spark plugs. If compression numbers are good then go to rebuilding carb and fuel pump.<br /><br />Your boat should run about 30 mph top speed. There is a plate on the lower unit just above the prop. This is called and anticavitation or antiventilation plate and it should be about even with the bottom of the back end of the boat.<br /><br />If motor sounds good at higer speeds but you can only do about 5 mph chances are your prop is spun. Props do not use shear pins. The use hard rubber and when they hit something the rubber separtates. The only way you can test for a spun hub is to take fingenail polish or a permanant marker and draw a line on the propeller and the prop nut at the very back of the propeller shaft.(yours is probably a cone with a cotter pin in it. Run the motor at high speed then look at prop to see if your marks still line up. If they dont you will need your prop rehubbed or you will need a new prop

 

[norenebeaver]

Re: '70 55hp Chrysler - minimal power - won't idle

Thanks euro - you are a wealth of information! I contacted SeaSwirl to get manuals for the boat but never heard back so will check the link you sent. When the motor was overhauled a year ago - would it be standard practice to rebuild the carb and fuel pump? I need to take a pic of this thing so you guys can see it - it's about as clean and neat as the day it came off the manufacturing floor. Will change the spark plugs - only regapped the ones that were in there already. Going to get a compression tester tomorrow. Wow - 30 MPH top speed - I would be thrilled - at least we could pull the girls on an inner tube at that speed and they won't go to sleep - LOL.<br /><br />The motor does sound good at WOT it just doesn't move so I will do the prop test as well - and your right its a cone and cotter pin. <br /><br />Starfire 65: We are not having any trouble with overheating at this point so we are lucky there.<br /><br />Are spark plugs supposed to get fuel on them? <br /><br />thanks for all the help guys! It's grealy appreciated....<br /><br />Blessings<br /><br />Norene

 

[eurolarva]

Re: '70 55hp Chrysler - minimal power - won't idle

your spark plugs should have a slight black grimy appearance them. You may have the wrong spark plugs in the motor. That could explain the gas on them. The plugs that chrysler recommends for that motor dont exist anymore and the L82C are cross referencedd over.<br /><br />On the rebuild. Here in Minnesota we use this oxiginated fuel which contains a lot of alcohal and water. The alcohal dries out the rubber and causes problems. The carb and the fuel pump seem to be supseptable to the fuel we use. I try and keep my gas can as full as I can using good quality marine outboard oil. Towards the end of the season I use fuel stabilizer in my gas so that it stays fresh over the winter. The gas you use on this motor should be 87 octane regular unleaded.<br /><br />Funny most chryslers are in pristine shape and look like they have never been used. I think if you have a spun hub that will take care of the power thing then the fuel thing should not be too hard to get your idle working. And not sure if it was mentioned but the carb does not have an air filter<br /><br />when you are trying to idle try pushing the choke when the motor tries to die. If that makes the motor run smoother you have a fuel problem and the fix is a simple rebuild. I would use the choke method to shift into forward instead of jamming into gear at higher rpm which can damage the lower unit.

 

[norenebeaver]

Re: '70 55hp Chrysler - minimal power - won't idle

Well boys - not sure what exactly we did but she's a runner..........I played with the throttle a little bit here at home but ultimately put it back to it's original position as it seems that was doing nothing. Bought a compression tester but wanted to wait till it was in the water to try it. We set out - got into the middle of the lake - my husband adjusted the screw that is above the carburetor opening. We turned it all the way clockwise as far as it would go - then back one full turn - started it - idled better so we did another half turn - made it worse so back a full turn - started and idled fine. Off we went - WOT and still no power - I started bringing the throttle back to neutral when something all of a sudden broke loose and off we went. We thought maybe we broke something - but nope - no matter what we did she kept continuing to work like a beauty!!! The old girl can certainly move!!!!!! Might even pull a skier - of small stature anyway. <br /><br />We are still having one small problem - she will idle, however she misses a little - will not attempt to die - just miss - I will check other posts to see if anyone addressed that problem.<br /><br />Thanks to Starfire65 and Eurolarva for all your suggestions!!!<br /><br />We are very proud of our 34 year old girl - she did good!<br /><br />Norene