Starting engine in garage

[bordercollie]

I'm thinking it would be nice to be able to start the engines (98 sportster) inside my garage (without jets attached, just for basic tuning purposes) b/c I don't want to work in the driveway, backing in/out ect.

Sooo, I know I need an exhaust extension, maybe something like this http://www.amazon.com/Crush-Proof-T...bs_auto_3?ie=UTF8&refRID=1A1G09XPGS2ZN3AGNPB8

(not sure if it will fit b/c I'm traveling at the moment without the boat)

Page 147 of the shop manual has a good diagram of the cooling system, it looks like I can attach a fresh water hose to the left engine inlet, and the right is the discharge?

My question is what should I do with the rear engine hose? Also, is some water going to cool the exhaust b/c I doubt those rubber elbows would last long otherwise?

Thanks

 

[bordercollie]

The rear water outlet on engine cover (facing fuel tank) appears to pass through exhaust housing? and then goes back into engine? And it looks like a small amount of water is added to the exhaust?

PDF wont let me cut and paste diagram from shop manual but all these 2 stroke engines probably work on same principle

 

[LouDoo]

Your idea is sound except you really can't run your engines for more than a couple of minutes because the carbon seals require cooling water, in theory if you can provide cooling water to the carbon seals you could run your boat for a longer period.

That being said there's really not much to tell with the boat on the trailer, it really needs to be in the water, under load, to tell how well or how bad it's running. So unless you have a test tank the best thing to do is take it to the lake. If you don't want to take it out on the lake just leave the boat strapped to the trailer and back the trailer into the water.

Here's a cooling diagram of a 787.

Lou

 

[Bonmotwang]

Even with a pipe for the exhaust, better to have garage door(s) wide open.
It saves lives!

 

[Bonmotwang]

Your idea is sound except you really can't run your engines for more than a couple of minutes because the carbon seals require cooling water, in theory if you can provide cooling water to the carbon seals you could run your boat for a longer period.

That being said there's really not much to tell with the boat on the trailer, it really needs to be in the water, under load, to tell how well or how bad it's running. So unless you have a test tank the best thing to do is take it to the lake. If you don't want to take it out on the lake just leave the boat strapped to the trailer and back the trailer into the water.

Here's a cooling diagram of a 787.

Lou

Is there one for 947 boat?


Sent from my iPhone using Tapatalk

 

[killer454]

I already rebuilt one engine have not even fired it up yet
this Thursday im ordering 2nd engine from sbt
when I get both engines in the boat and shimed right with the tool I will be checking engines and electrical for trouble
I will not even have my pumps on the boat-I will make sure they are ideling at 3000 rpm and check for cooling leaks while on the hose
im thinking the carbone seal is on the driveshaft so it should not effect me from just running my engines right?

 

[Guest_User]

3000 rpms out of the water is not exact and accurate. some engines that idle in the water @ 1500 (spec) will run anywhere between 3000-3300 out of the water. so set your boat up to idle @ 1500+ in the water and don`t waste time otherwise. There is a set point to adjust carbs for idle in the shop service manual, this is a good starting point and go from there.

as Lou said. no load is not really good for these engines. even the driveshaft, tension on the carbon seal and impeller shaft running in oil is a slight resistance.
make dam sure you can shut the engine down in a run-a-way situation if it gets away from you...

 

[bordercollie]

Hey Lou thanks for the reply. I'm traveling at the moment so checking in here is hit and miss.

Yes I would be attaching a fresh water line to the left hose on top of motor facing impeller. The right hose appears to be the exit which I will drain off in yard.

But there appears to be a rear hose that I'm not entirely sure about, it looks like water is added to exhaust for cooling? Page 147 of the shop manual has a pretty good diagram (PDF wont let me copy)

Anyhow, I'm thinking maybe $50 worth of tubing and an exhaust hose should work......the garage door will be open obviously but I just don't know how much tuning/tinkering I will need to do and don't want to work in the driveway.

Also the driveshaft will be disconnected, I know final tuning needs to be done under load I just want to get the engines running smooth

Thanks Everyone!

Your idea is sound except you really can't run your engines for more than a couple of minutes because the carbon seals require cooling water, in theory if you can provide cooling water to the carbon seals you could run your boat for a longer period.

That being said there's really not much to tell with the boat on the trailer, it really needs to be in the water, under load, to tell how well or how bad it's running. So unless you have a test tank the best thing to do is take it to the lake. If you don't want to take it out on the lake just leave the boat strapped to the trailer and back the trailer into the water.

Here's a cooling diagram of a 787.

Lou