7.5 hp Evinrude 1954

[freddyray21]

1954 Evinrude 7.5 hp. Motor pumped water good when I first got it, but lower unit was full of water. I pulled the lu and resealed it also putting in a new impeller. Now it won't pump. I know the impeller is working as I pulled the power head again and used a drill to turn the drive shaft. I have a very good flow out of the tube. The only thing I can think of is something got into the water passages. The old impeller was in good shape no pieces so it's not that. I did use a bit of sealer on the power head gasket when I put it back together probably stupid seeing my current issues. Do I need to pull the head to find what is blocking it? I pulled the side cover and did not find anything in there.

 

[wavrider]

Re: 7.5 hp Evinrude 1954

Make sure the tube is in the grommet on the waterpump, you may be pumping water into the exhaust side of the lu instead of into the head.
I do not think sealant would make that great of a difference on the head gaskets, try hooking a water hose to the water tube going into the power head and see if water flows out the exhaust, you would have to drop the lu to do this.

 

[freddyray21]

Re: 7.5 hp Evinrude 1954

just a bit frustrated and I guess it is my fault. I have pulled the power head and while I had it off used a drill to spin the driveshaft and the water pump is working! I have a good flow from the barrel up to the power head. I could not have a better flow as the tube won't let any more water through so I know the tube is hooked to the water pump. It is just not going through the block.

 

[wavrider]

Re: 7.5 hp Evinrude 1954

Looks lke you may be pulling the head gaskets to see where the clog is,

try using compressed air to blow through the water passageways
probaly got some critters nest up in there

 

[freddyray21]

Re: 7.5 hp Evinrude 1954

don't think it's a critters nest. It pumped water fine all through the block prior to resealing the lu. It is something I did or didn't so when I reinstalled the powerhead. I have done several of these before and have never had this problem.

 

[wavrider]

Re: 7.5 hp Evinrude 1954

then if nto head stopped up
possible the impeller is not on the key? or sealed up the water inlet passage way in the lu,
I would take the water pump housing off and re install the water pump assy and inspect everything in the lu,
either impeler is not on the key way, key is sheared or the inlet passage is stopped up

some of the impeller kits have keys that do not work with the older engines pay close attention to the key, measure the depth of the groove in the shaft with a nail and ensure the key will work in that application, may have to use a different key or the original

if it pumped fine before then it has to be in the water pump and not the power head

 

[freddyray21]

Re: 7.5 hp Evinrude 1954

I am sorry but you are not reading my post. I REPEAT. I HAVE LEFT THE LOWER UNIT ON AND PULLED THE POWER HEAD. I HOOKED A DRILL TO THE DRIVE SHAFT AND THE WATER PUMP IS WORKING. I HAVE EXCELLENT FLOW FROM A BARREL TO THE POWER HEAD. JUST NOTHING THROUGH THE POWER HEAD.

 

[wavrider]

Re: 7.5 hp Evinrude 1954

IF the power head is not stopped up, if the lu pumps water, than where is the problem.?

QUOTE from your first post " only thing I can think of is something got into the water passages"

I am reading your posts, and the only thing I can think of is to reverse every maintenance procedure you did until YOU can find the problem that is stopping the water flow.

If the power head is not stopped up, did you verify this by putting a hose in the tube and running water up through the power head?

you verified the lu pumps using a drill

there is only one part betwen the power head and the lower unit, the shaft running from the power head to the lu which the impeller fits on with a key.

you are the eyes and ears, I can not see what you have or have not done.
If it worked fine before, and it does not work now, then somewhere somehow something is not correct in the procedure that was used in this maintenance.

I did not observe you perform the maintenance so I can not tell you what is correct and what is not correct, I can only suggest possibilities based on what you are informing the board.

I know it can be frustrating, we have all run into something that makes us scratch heads.

I hope you find out whatever it is, hopefully some of the experts will reply.

 

[freddyray21]

Re: 7.5 hp Evinrude 1954

I am sorry to have been short, but logically if I can put a drill on the driveshaft and get water out of the tube at the top of the leg then the impeller is on the key, it is turning, and the tube is not clogged. I guess what I was looking for was someone who might have had the same experience and could tell me what they did. I did find a possible answer over at the AOMCI site. Apparently there are two small holes in the water pump housing that if clogged will cause it to fail once the powerhead is attached. I will check those tomorrow and see and let this board know the answer. I've not done as many as other's, but I've done several and have never had this problem.

 

[wavrider]

Re: 7.5 hp Evinrude 1954

No offense taken here, it can get frustrating.
Step by step process until you eliminate every possible cause, you will eventually find the problem, dedication and commitment will result in success.

Try running the hose through the waterpump outlet where it connects to the tube, back flushing the waterpump to see if water comes out the pickup screen.

run the hose up the water tube into the power head to make sure it flushes well.

eliminate the easy steps before tearing into anything with the wrenches, you will find it, it will be something simple, and with the knowledge gained from this adventure you will be able to asist others in the future when they have this problem

that is what is great about this forum, knowledge, experience and the willingness to assist others.

 

[freddyray21]

Re: 7.5 hp Evinrude 1954

pulled the head today and am putting a new head gasket on it. All the passageways are clear in the block. I am going to put the old impeller back in it just in case the Sierra impeller is the problem. Never had one bad, but I have heard they do come that way.

 

[samo_ott]

Re: 7.5 hp Evinrude 1954

But if you hooked up the drill to the LU and it pumped well, unlikely it's the impeller. But at this point I guess you have to try.

 

[HighTrim]

Re: 7.5 hp Evinrude 1954

Also doubt it is the impeller.

Does that model have a t stat? I dont think so, but if it does has it been tested to ensure it is not stuck closed?

Only other thing I can think of would be the water tube grommet(s). With the lu off and spinning off the drill, all seems well, then when the water tube is inserted into the grommet, it is know to slip,or is swelled, restricting water flow. May want to ensure this is not the case.

 

[freddyray21]

Re: 7.5 hp Evinrude 1954

I left the lu on the leg. This model you have to remove the power head to get to the shift linkage so with the drill I have water all the way up to the power head through the tube. I did have a question though. On the drive shaft there is a stack of parts. For lack of a better description a cup which sets on the pin in the driveshaft, then a spring, a second cup, then a brass thrust plate which rides against the powerhead. Mine also had a large rubber washer. Is the washer supposed to go between the thrust plate and the powerhead and could this be my problem?

 

[chief97]

Re: 7.5 hp Evinrude 1954

New to this Forum, but have a question concerning a 1954 7.5 Evinrude that my father bought brand new and passed down to me. It runs great and I have the orginal gas can, but the metal is showing signs of age and fatigue. I would like to convert to the new single line setup. I have read quite a few of the conversions done on larger new motors (1958 and on). Has anyone ever done it to a 1954 7.5 Evinrude and if yes, how?

 

[jbjennings]

Re: 7.5 hp Evinrude 1954

http://www.duckworksmagazine.com/05/columns/max/5/index.cfm

forget what I wrote below. Above is a link to show you ONE way it can be done. It works fine. There are other, perhaps better ways.
Good luck,
JBJ


I've done it on a '55 7.5hp. What I did was follow the instructions on the duckworks.com magazine article by max warcziniak or however you spell his name. Basically, you remove the intake manifold, take out the check valves which cause constant pressure on the little nipple going out of the intake to your pressure tank. You then use a little vaccuum line plug to block off one of the check valve holes. When you reinstall the intake, this gives you a pulse vacuum which you can use to run any pulse vacuum fuel pump. Most folks like mikuni. I used a plastic briggs and stratton lawn mower 3-line pulse vaccuum pump I got at the local lawn mower shop because it was handy. I actually got two pumps at once and did the same on my '53 johnson 10hp, so I'm sure it will work on your '54. I'll try to find the article on duckworks and give you a link. In the future, if I ever do it again, I'll probably just drill and tap one of the bypass covers and install a nipple to use for the vaccuum. There's actually several threads on how to do a fuel pump conversion if you look.
Later,
JBJ

 

[F_R]

Re: 7.5 hp Evinrude 1954

Here is how I do them. No need to tear into the reed plate. And it looks good, where OMC meant the pump to be placed.

 

[chief97]

Re: 7.5 hp Evinrude 1954

Thanks for the information, this is the instruction I needed to do the job. Appreciate it.

 

[WATERTIMES]

Re: 7.5 hp Evinrude 1954

Hey F R
Where did you get your pump from ? I've got the '55 same hp, would that pump be the same ? What was the total cost of conversion ?? I'm extremely interested in doing the same.What parts were needed to do all ? NEEEET !!

 

[F_R]

Re: 7.5 hp Evinrude 1954

That is a used pump from that era. But a modern pump will work just as well. See the 18-7350 sold here at iboats.

I make the adapter plate. It's against the rules here to say that I sell them, but you can make your own.

You need a pump, gaskets, screws, hoses and clamps, and a single line fuel connector. The pump is the most expensive part, around $45 new. Or, there are used ones. A new fuel connector is overpriced but the same one was used for many years and they are on junker motors all over the place.

Send me a PM if you need more information.