Lehr 9.9 HP Propane Issues

The 9.9 HP Lehr engine won't start, unless I bleed it for 5 or 7 seconds.



This happens Cold, or Hot, every start. The battery is new, and fully charged. There is a solar controller and volt meter I can read inside the boat. I started trouble-shooting the battery first.


https://imgur.com/a/Jc5nOiZ Thanks!

Welcome aboard. Are they still making them?

Nope, out of business, and no help anywhere. I'm left to begging the internet to help me!

I purchased a Merc 5HP propane after almost getting a lehr.

I see you found the bleed method to overcome this. Some people have drilled a hole in the cowel to make it easier.
IIRC there is a part in the carb? location that needs replacing as it allows propane to bleed off or such. I did read an article during the research, found out these were being dumped on the market after a large bad batch from China broke the company on warranty.
There was a source for the parts as it fits another brand. All I recall on this.

Greetings,
Mr. AC. Welcome aboard, as well. Hmmm...In your first video, the motor is turning over WAY too slowly IMO. I don't know if there is some sort of control that is cutting out due to lack of propane pressure or if you have an electrical problem. The two may be unrelated (slow crank/no start due to no fuel). Just an observation.

Thank You Soo-Valley! This lead gives me something to research.

We have a much neglected Lehr 9.9 on our swim step. Have had it for maybe 7 years, I think. Only fire it up several times per year to make sure it works and after changing oil. It's there as an emergency get home, or at least to a safe spot, outboard if the main engine ever dies.

Turn propane on...purge a bit...set throttle a bit past where they recommend...pull twice on cord...and it starts. Restarts right away. Still on original tank of propane with no refills.

Don't have an electric start.

Could you have a small hole in the propane tank hose?

I've checked the hose with soapy water, and it has no leaks. Do you have a liquid draw tank or a regular vapor tank? There is too much pressure until I bleed the carburetor, then it will turn over and start.

It's a regular liquid on bottom, draws gas from the top kind of tank.

Don't know what you mean by too much pressure. I purge the air in the lines...get propane to the engine...then it starts every time.

Sorry, I'm no mechanic!

I've described it the best I can, I'm no mechanic either!



This does help. I'm using a liquid draw propane tank, I might try a regular one!

I had 3 carburetors replaced under warranty. They are a cheap peace of $hit! Being OCD, I decided to disassemble one of the POS and figure out if I could repair it with better materials. Basically the POS is 2 regulators to reduce tank pressure to a very low stable pressure and then a demand valve will a diaphragm that opens with vacuum from the engine. The components are of such poor quality, it would have been easier to use an external regulator and try to improve the diagram material.

To your question, on the side or bottom of the unit is a square plate with a round raised area that is held in place with 4 screws. In the center of the plate is a small hole. After turning the propane on, you can insert a small blunt object to push the diaphragm to quickly purge the fuel line to propane. You can hear the hissing and the sound changes when you get to propane.

The other issue with these gems is that most of the aluminum isn't a marine grade alloy. Using the unit in salt water corrodes the water cooling passage ways.

Ted

O C Diver said:

...To your question, on the side or bottom of the unit is a square plate with a round raised area that is held in place with 4 screws. In the center of the plate is a small hole. After turning the propane on, you can insert a small blunt object to push the diaphragm to quickly purge the fuel line to propane. You can hear the hissing and the sound changes when you get to propane....

Ted

Click to expand...

Photo here, with an edit...purge for only 5 seconds or so:

https://www.trawlerforum.com/forums/showpost.php?p=165883&postcount=1

Boy, your video sure sounds like a fluid lock in the cylinders, too much compression. Can this be? Or a tired battery?

When they first came out I was enamored of the Lehr propane outboard. The reviews were lousy and then the went out of business. Glad I didn't jump in too quickly.

pete

O C Diver said:

I had 3 carburetors replaced under warranty. They are a cheap peace of $hit! Being OCD, I decided to disassemble one of the POS and figure out if I could repair it with better materials. Basically the POS is 2 regulators to reduce tank pressure to a very low stable pressure and then a demand valve will a diaphragm that opens with vacuum from the engine. The components are of such poor quality, it would have been easier to use an external regulator and try to improve the diagram material.

To your question, on the side or bottom of the unit is a square plate with a round raised area that is held in place with 4 screws. In the center of the plate is a small hole. After turning the propane on, you can insert a small blunt object to push the diaphragm to quickly purge the fuel line to propane. You can hear the hissing and the sound changes when you get to propane.

The other issue with these gems is that most of the aluminum isn't a marine grade alloy. Using the unit in salt water corrodes the water cooling passage ways.

Ted

Click to expand...

^^^That is it, replace the diaphragm, that is what I read was the problem and what solved most hard start. Purging works to free it up, it sticks or is not plyable, tried finding a reference but have not. So going on memory. It was to do with carb being replaced and then someone just replaced diaphragm.
That was not the only common problem, there is something else may come to me where slow cranking was involved.

They seemed like a good idea but apparently not.

Comodave said:

They seemed like a good idea but apparently not.

Click to expand...

They are a very good idea. Fuel that doesn't go bad. No water possible in the fuel tank. In a pinch, you can use the same tank to run your gas grill. Tohatsu makes a 5 HP version. Don't know what the quality is or whether they will expand the line.

https://www.tohatsu.com/marine/int/outboards/mfs5c-lpg_1.html

Ted

Here are sailboaters talking about Lehr
https://forums.sailboatowners.com/threads/first-problem-with-lehr-outboard.153709/
Here is a manual in case you do not have
http://golehr.com/downloads/LEHR_9_9_Operators_Manual.pdf

O C Diver said:

They are a very good idea. Fuel that doesn't go bad. No water possible in the fuel tank. In a pinch, you can use the same tank to run your gas grill. Tohatsu makes a 5 HP version. Don't know what the quality is or whether they will expand the line.

https://www.tohatsu.com/marine/int/outboards/mfs5c-lpg_1.html

Ted

Click to expand...

I should be starting the 5HP Merc made by Tohatsu for the 3rd time in a few weeks. So far impressed with the build.

It looks like there is a work-around, and no real fix!

Soo-Valley said:

I purchased a Merc 5HP propane after almost getting a lehr.

I see you found the bleed method to overcome this. Some people have drilled a hole in the cowel to make it easier.
IIRC there is a part in the carb? location that needs replacing as it allows propane to bleed off or such. I did read an article during the research, found out these were being dumped on the market after a large bad batch from China broke the company on warranty.
There was a source for the parts as it fits another brand. All I recall on this.

Click to expand...

Would drilling a whole in the cowl, allowing for easy pin access to release the propane, have enough ventilation?


Maybe a little hinged door on the side?

O C Diver said:

They are a very good idea. Fuel that doesn't go bad. No water possible in the fuel tank. In a pinch, you can use the same tank to run your gas grill. Tohatsu makes a 5 HP version. Don't know what the quality is or whether they will expand the line.

https://www.tohatsu.com/marine/int/outboards/mfs5c-lpg_1.html

Ted

Click to expand...

I've asked around to anyone who would listen, especially people I see with Tohatsu engines, about my issue.


ALL the Tohatsu owners I have run into, love theirs!

AlleyCat said:

Would drilling a whole in the cowl, allowing for easy pin access to release the propane, have enough ventilation?


Maybe a little hinged door on the side?

Click to expand...

Sorry, I have not done that so cannot say, only passing on what I have read. Speaking of which, I have tried to find links that were readily available a few months ago, cannot. If purging works then live with doing that, if not see if you can get the carb rebuilt or just change the diaphragm.

Having to purge the line after the engine has sat for a while or after the hose is disconnected from the tank is normal. Air gets into the system. Once the engine has started you should be able to stop it and restart it all day long.

It should run fine on either a gas feed tank or liquid feed tank. It has a vaporizer in the system. In fact on a really cold day a gas feed tank might not supply enough propane to give you full power from the engine. I run my 15 on a forklift liquid feed tank.

The starter sounds weak. Have you tested the voltage at the starter? I’m thinking voltage drop between the battery and the starter. That one uses an external battery doesn’t it? You could get them with a small battery under the engine cover.

What happens when you hand crank it?

I think I have a pdf of the service manual. If you will PM your email to me I’ll try to send it to you. Probably not much help without parts being available.

Definitely not enough volts to the starter. Get that sorted first.

HopCar said:

Having to purge the line after the engine has sat for a while or after the hose is disconnected from the tank is normal. Air gets into the system. Once the engine has started you should be able to stop it and restart it all day long.

It should run fine on either a gas feed tank or liquid feed tank. It has a vaporizer in the system. In fact on a really cold day a gas feed tank might not supply enough propane to give you full power from the engine. I run my 15 on a forklift liquid feed tank.

The starter sounds weak. Have you tested the voltage at the starter? I’m thinking voltage drop between the battery and the starter. That one uses an external battery doesn’t it? You could get them with a small battery under the engine cover.

What happens when you hand crank it?

I think I have a pdf of the service manual. If you will PM your email to me I’ll try to send it to you. Probably not much help without parts being available.

Click to expand...

I have both the PDF and original paper manual I got with the engine. My version of the engine has an external battery, with no alternator. I run a solar panel, and controller, so it has enough voltage.



(A later version of the Lehr had an alternator, and small starter battery inside the cowl.)


If I purge the propane in my start procedure and turn the key, it will start 10 times in a row.


https://imgur.com/a/Jc5nOiZ


"Purge, Turn Key, Starts like in the second video."



"No Purge, Turn Key, Won't start, like in the first video."



"Purge, Turn Key, Start like in the second video."



I can go back and forth purge, no purge, and the results are consistent. The battery will start only after a purge. I have spent over half an hour going back and forth, because I've tried every shut down procedure I could think of, and tried to start it with out bleeding it.



It doesn't start, then I bleed it, start it, and try a new shut down procedure.



Bleeding it is the only thing that works!

Ski in NC said:

Definitely not enough volts to the starter. Get that sorted first.

Click to expand...

I have enough volts to the starter. It always starts after a purge.



Ten out of ten, starts after a purge. I'd like to get a fix that doesn't require removing the cowl, inserting a pin into the plate here like MurryM illustrated


https://www.trawlerforum.com/forums/...83&postcount=1


releasing the pressure, and then turning the key.

Alleycat the manual I offered to send you is the service manual and parts list that mechanics use. It is not the owner’s manual.

I knew Bernardo the owner of Lehr. I had suggested they add an external purge button but they never did. Bernardo was obsessed with making larger and larger engines. He should have stopped after the five hp and concentrated on quality control. The 15 was as big as he should have gone. He spent a lot of time and money developing a 25 that would have needed a huge tank. I don’t think there was a market for the 25, even the 15 was pushing it. He should have also made the five and ten hp with a 25” shaft for sailboat auxiliary.

I don’t think you are lowering the pressure when you push the purge button. You are letting propane flow through the system and push air out. The question is why is air getting into the system?

Check the voltage at the starter while it is actually cranking. Also at the battery while cranking.

Slow cranking indicates either a battery problem or a dirty contact problem in the circuit which creates a Vdrop under load.
That could mean the ingnition system is not developing its proper voltage so the spark is either non-existant or too weak for a quick fire up..
I don't think your Lehr ignition is battery powered but if the spin while cranking is too slow the flywheel mag. may not generate a strong spark.

Don't assume just because you have a solar panel that the battery or the wire connections are ok and the power is getting to the starter.

HopCar said:

Alleycat the manual I offered to send you is the service manual and parts list that mechanics use. It is not the owner’s manual.

I knew Bernardo the owner of Lehr. I had suggested they add an external purge button but they never did. Bernardo was obsessed with making larger and larger engines. He should have stopped after the five hp and concentrated on quality control. The 15 was as big as he should have gone. He spent a lot of time and money developing a 25 that would have needed a huge tank. I don’t think there was a market for the 25, even the 15 was pushing it. He should have also made the five and ten hp with a 25” shaft for sailboat auxiliary.

Click to expand...

I sent you my E-mail in a private note. The service manual would illuminate a lot of things I don't have a good understanding of!



My model is the long shaft, and I agree with you, the 5 and 9.9 should have been used to get the technology right.


I think Bernardo has become a joke. He still list on his linked in page that he's currently the CEO of Lehr. He should put a notice on golehr.com that they are no longer supporting products, not leave customers wondering!