1958 Evinrude 7-1/2 Fleetwin carburetor overhaul

[khe]

I'm in the process of overhauling the carburetor on a 1958 Evinrude 7-1/2. I purchased carburetor kit #439071 from my local dealer. There are some parts in the kit that were not in the carburetor I disassembled - there are some translucent plastic washers which I believe go between the packing washers and the packing nut around the high and low speed jets. There is also a tiny cotter pin which I believe is for the throttle linkage. The original clip was an "S" shaped wire.

There is also a red, plastic washer that I am not sure where that is used.

Thanks.

 

[kbait]

That kit is used for 2-25hp for many years.. you will have extra parts..

 

[khe]

Thanks kbait. I'm pretty sure the dealer told me to install the plastic washers between the packing washers and the packing nut and that the original carb. wouldn't have them.

The red washer must be for some other application.

I am going to see if the tiny cotter pin can be used to retain the throttle linkage. I need to go back to the dealer tomorrow for a fuel filter bowl gasket - there was not one in the kit for the glass bowl. The original was dry-rotted which was no surprise since the motor is 62 years old and hasn't been run in almost 40 years

 

[F_R]

Thanks kbait. I'm pretty sure the dealer told me to install the plastic washers between the packing washers and the packing nut and that the original carb. wouldn't have them.

The red washer must be for some other application.

I am going to see if the tiny cotter pin can be used to retain the throttle linkage. I need to go back to the dealer tomorrow for a fuel filter bowl gasket - there was not one in the kit for the glass bowl. The original was dry-rotted which was no surprise since the motor is 62 years old and hasn't been run in almost 40 years

Correct.
And yes they originally used wire to secure the linkages

 

[racerone]

The red washer ( 1/4" inside diameter ) is for the drain plug on much newer carburetors.----Not used on yours.

 

[khe]

For the first time in over 40 years, it runs! I didn't run it long because I noticed it wasn't pumping water. Looks like I need to put a water pump impeller in it. It also appears to be leaking gear oil where the lower unit bolts to the upper. I don't know if there is a seal there but It's time to pull the lower unit. The vent plug is 3 inches below the joint where the lower unit meets the upper. Is it necessary to drain the gear lube to separate the lower unit?

On the 7-1/2 Fleetwins, the power head must be removed in order to gain access to the shift linkage.

I am sure once I get into the water pump, I'll find the vanes are rotted or sheared off.

I need to replace the o-rings in the motor side of the fuel tank hose - when I unplugged the fuel line, it kept leaking from the hose end.

 

[Crosbyman]

http://www.youtube.com/watch?v=SVOedhzPP7M

"It also appears to be leaking gear oil where the lower unit bolts to the upper" ... probably just sludge leaking out


"For the first time in over 40 years it runs"

great news but... better pull the flywheel and inspect for cracked coils and redo all electricals ... coils if originals and cracked....points condensers plug wires


lots of good utubes

http://www.youtube.com/watch?v=ga1Cjymj6ms&feature=youtu.be

https://bit.ly/2wqMPTb oldies bible

 

[khe]

I read Joe Reeves' post on dialing in the carburetor and have some questions:

• With the high speed needle opened one turn and the low speed needle opened 1-1/2 turns, should the knobs be installed with their pointers in the 12:00 position?
• Are the subsequent adjustments to dial in the carburetor performed using the knobs or are the knobs installed after dialing in the needles and placed in the 12:00 position?

I need to repair the water pump first but wanted to have the carb. information so I can prepare for that task.

 

[oldboat1]

agree with Crosbyman's post (though haven't checked the uTubes -- probably helpful ones). In practice, you will probably find that the initial setting is closer to half or 3/4 for the h.s. needle, and probably 1 or just a little more for the l.s. setting. But the object is to get it running so you can fine tune it. After you find the best settings, the knobs should be placed to allow you to turn the needle either way before hitting the stop. What number is up or down is immaterial, except to help you decide if the needle has moved (make sure the jam nut behind the knob is tightened enough to keep the needle from vibrating loose.)

 

[khe]

agree with Crosbyman's post (though haven't checked the uTubes -- probably helpful ones). In practice, you will probably find that the initial setting is closer to half or 3/4 for the h.s. needle, and probably 1 or just a little more for the l.s. setting. But the object is to get it running so you can fine tune it. After you find the best settings, the knobs should be placed to allow you to turn the needle either way before hitting the stop. What number is up or down is immaterial, except to help you decide if the needle has moved (make sure the jam nut behind the knob is tightened enough to keep the needle from vibrating loose.)

Thanks for the response. Based on that, when I get it out on the water to dial it in, I'll remove the knobs since there is a stop to limit the travel to 1/2 turn each way. Once it's dialed in, I'll install the knobs with the pointers in the 12:00 position so it can be adjusted/tweaked during operation.

 

[oldboat1]

Sounds right. Adjustments are small (1/8 to 1/4 turn at a time). I find the h.s. needles easier to set -- done at WOT or thereabouts, and the rpm changes are pretty obvious. The l.s. needle might be a little tougher. I usually adjust clockwise (leaner -- more air, less fuel), until the engine lean sneezes or stalls (then back out about 1/4 turn.) After setting the h.s. needle, do a final readjustment of the low speed mix and you should be finished.

 

[khe]

Thanks for the information. For some reason, I am not being notified of new posts even though I have the notification turned on.

This weekend, I hope to drop the lower unit to see what's going on with the water pump and determine what parts to order. Once I have it pumping water, I can then get it on a boat and adjust the carburetor.

 

[khe]

I was able to get back on this project the other day. Pulled the lower unit to replace the water pump impeller and discovered why it wasn't pumping water - one of the fins was broken off the impeller. The worst part of the whole job was to clean the 62 year old gasket from the powerhead. It was like stone.

I got it all back together and filled it with gear oil and then ran it in a barrel yesterday. I finally got it started and it was pumping water but it ran poorly - the carb settings were at the default initial settings and I need to dial them in. The fuel line is loose at the tank which I think may be contributing to the problem. I need to get some new clamps and fix the hose connections at the tank.

I bought new o-rings for the opposite end of the hose which I plan to install this evening.

The dealer said the curved zip ties are fine to use on the hose connections but the originals are metal. I'm concerned I might not be able to get the zip ties tight enough. The OE part no for the clamps is 301822 but what tool is used to crimp them? I made a tool for crimping the shift cable bellows clamp on a MerCruiser stern drive by welding a 1/2" nut to a cheap pair of pliers, then drilling the nut with a 1/2" drill bit, then sawing the nut in half. Is there a similar process for these clamps?

The barrel had a lot of black sludge floating on top of the water. I verified it is not gear oil and it smells like the motor exhaust. Could this be due to the motor running rich due to not having the carb dialed in?

 

[Crosbyman]

sludge is normal just..... unburnt oil carbon fuel etc.....

 

[oldboat1]

Try using a bladed screwdriver and a needle nosed pliers to install the plastic ties. Use the screwdriver as a fulcrum, holding the tie firmly in place, and pull the tie tight with the pliers.

 

[Crosbyman]

the smaller hose clamps do a good job to and easy to screw down tight

CAA48 - American hose clamp [62048] - $1.84 : Bel-Metric, Metric Hardware, Metric Fasteners, Metric Bolts, Metric Nuts & Time-Sert Thread Repair

Bel-Metric CAA48 - American hose clamp [62048] - SAE Size #48 American BREEZE Power-Seal Hose Clamp Metric Clamping Diameter Range: 65mm to 89mm Inch Clamping Diameter Range: 2-9/16 to 3-1/2 OEM# 62048 General purpose worm-gear automotive and industrial clamps. High strength 4-piece Quadra-Lock...

www.belmetric.com

 

[khe]

Try using a bladed screwdriver and a needle nosed pliers to install the plastic ties. Use the screwdriver as a fulcrum, holding the tie firmly in place, and pull the tie tight with the pliers.

That's what I did. I trimmed the ends of the hoses first and they were much tighter going over the fitting. I need to buy a couple more ties so I can get the tank end fixed.

I was surprised the o-rings in the hose fitting weren't like stone - they were actually soft and pliable but since I had new ones and the connector was apart, I changed them.

 

[khe]

I read the procedure on adjusting the high and low speed jets and it says to adjust the high speed jet first, then the low speed. Is that due to some interaction between the high and low speed mixture adjustments that requires the high speed to be adjusted before the low speed?

Is there a reason the low speed couldn't be adjusted first, then the high speed, then repeat the low speed adjustment?

 

[racerone]

That is the correct procedure.----All the fuel ( including idle fuel ) comes through the high speed jet !!

 

[khe]

That is the correct procedure.----All the fuel ( including idle fuel ) comes through the high speed jet !!

Thanks! I knew there was a reason the high speed needed to be adjusted first. It is supposed to be in the mid 60s here this weekend and it would be nice to get this motor done and prepped for storage.