Jump to content

Welcome to TheMalibuCrew!

As a guest, you are welcome to poke around and view the majority of the content that we have to offer, but in order to post, search, contact members, and get full use out of the website you will need to Register for an Account. It's free and it's easy, so don't hesitate to join the TheMalibuCrew Family today!

Shower/ Hydrolocking engine


Lance B. Johnson

Recommended Posts

So I posted this a couple of months ago...I still don't have a resolution.

We have used the shower only a couple of times. Both times the shower caused the engine to hydrolock. As far as I can tell, when the shower is turned on and the shower head is off, the pump cycles on and off occasionally and it forces water into the cooling system filling up the manifolds and then draining into the cylinders through the exhaust valves. This engine has NEVER hydrolocked any other time except for the two times right after the girls used the shower. Another member I know of has had the same issue.

According to the directions included with the shower, it is installed correctly though I did not do the installation.

Does anyone have a fix for this?

Link to comment

what symptoms is it showing to make you think it has hydrolocked?

So there is supposed to be a check valve huh? Funny, that is exactly what I was going to use to try to fix the problem if I did not get a better response.

Thanks,

Yup hydrolocked. Pulled all the plugs and cranked the engine to clear the water.

Link to comment

So there is supposed to be a check valve huh? Funny, that is exactly what I was going to use to try to fix the problem if I did not get a better response.

Thanks,

Yup hydrolocked. Pulled all the plugs and cranked the engine to clear the water.

You dodged a bullet, I had to replace my motor cause of that

Link to comment

You dodged a bullet, I had to replace my motor cause of that

No kidding huh? I hopped in the boat, turned the key and instantly new it she was locked up. Pulled the plugs, cleared it and ran it, checked the oil and ran it hard the rest of the day. Next day I went out for the morning ride worked perfect. Girls were waiting at the dock for a morning shower. An hour later it was time to surf and she was hydrolocked again. Cleared it again and ran it hard daily for the next week and a half and never had a problem (the girls were a little miffed at losing the shower though ROFL.gif )This was the very first time we had EVER used the shower.

I never told them that it would be okay as long as they turned the pump off, I did not want any accidents as I was already pushing my luck.

Link to comment

No kidding huh? I hopped in the boat, turned the key and instantly new it she was locked up. Pulled the plugs, cleared it and ran it, checked the oil and ran it hard the rest of the day. Next day I went out for the morning ride worked perfect. Girls were waiting at the dock for a morning shower. An hour later it was time to surf and she was hydrolocked again. Cleared it again and ran it hard daily for the next week and a half and never had a problem (the girls were a little miffed at losing the shower though ROFL.gif )This was the very first time we had EVER used the shower.

I never told them that it would be okay as long as they turned the pump off, I did not want any accidents as I was already pushing my luck.

It cost me close to 7 big ones to have a new motor put in, plus the down time. don't take anymore chances, you know the 3 strike rule.

Link to comment

Are you missing a one way check valve on the install kit? Follow the line's and figure out how the water is pressuring up the Ext port.

So there is supposed to be a check valve huh? Funny, that is exactly what I was going to use to try to fix the problem if I did not get a better response.

Thanks,

Yup hydrolocked. Pulled all the plugs and cranked the engine to clear the water.

There is not a one way check valve for the shower system?

Something is plumbed wrong, the shower would be taking water from the engine not pushing water into the engine.?

Post pictures where you have everything plumbed, including the mixer valve and pump. Something has to be crossed up some where?

-Paul

Link to comment

There is not a one way check valve for the shower system?

Something is plumbed wrong, the shower would be taking water from the engine not pushing water into the engine.?

Post pictures where you have everything plumbed, including the mixer valve and pump. Something has to be crossed up some where?

-Paul

I had the shower manual on the trip with me. I went through the manual and it looked right? I will try to get some pics up soon.

Link to comment
  • 1 month later...

Is the shower pump plumbed backwards?

I just ripped all of the lines out on my pump and replaced with larger lines. I didn't have any check valves to begin with. Are you guys saying there should be a check valve in there. I definitely don't want to be replacing an engine over a wrong shower set up.

Link to comment

I just ripped all of the lines out on my pump and replaced with larger lines. I didn't have any check valves to begin with. Are you guys saying there should be a check valve in there. I definitely don't want to be replacing an engine over a wrong shower set up.

There is no check valve on the showers, something is hooked into the wrong place.

Terry

Link to comment

Lets start with the basic's. Who's kit do you have? What model engine do you have so I can tell you where you are suposed to be getting the water supply from. That being cold water and hot water. Do you have cold water only and do you have hot water only? I mean that when both valves are closed and you open one at a time does it operate in respect to what valve you open?

Link to comment

There is no check valve on the showers, something is hooked into the wrong place.

Terry

Thanks, thats what I figured. It is still amazing that is happening. Think about the pressure the boats water pump is putting off. I looked at my shower pump and it is a maximum of 30 PSI. Even if it was plumbed backwards it seems hard to believe that small pump could overpower the engine driven pump. Just my thoughts

Link to comment

in a healthy engine the t-stat housing provides some small amount of water to the exhaust manifolds to cool down the exhaust gas enough to be carried by the rubber exhaust hoses and (?fiberglass?) muffler, if installed. as far as i'm aware, this is the only cross over that is going to allow water into the cylinders (through exhaust valves). there isn't any other circuit for water from the shower, raw water pump, circulating pump or water jacket into the cylinders, given healthy pieces and parts.

i have a hard time understanding how the low (30psi) pressure (correctly or incorrectly installed) shower pump could overcome the pressure created at an open exhaust valve while the engine is running so i'm going to assume the engine is off for this wag.

if the shower were incorrectly installed i could believe that it was pumping water from the engine water jacket (hot supply) then incorrectly returning it to the hose that runs from the output of the circulation pump into the tstat housing (a potential/intended cold water pick-up point although mine in plumbed between the raw water pump and the circulating pump). without engine run i suspect that the water could weep through the exhaust manifold back into (at most two) open exhaust valves. no more than two exhaust valves are open at the same time, right? BUT this scenario does not allow for an (apparently) functional shower.

a check valve might prevent this problem but i just don't see how a correctly installed shower could create the problem.

please be sure to share what you find.

Link to comment

As mentioned, a plumbing diagram and/or photos of each connection is needed to diagnose this properly. A standard shower installation does not pressurize anything except the shower head, and only pulls water from raw water intake hose and engine block drain port. Assuming this is a 5.7 block.

Peter

Link to comment

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...