Where to put flush T?

[TruckDrivingFool]

Well I became a man yesterday and replaced the impeller. I'm hoping to take the boat to the lake this afternoon to test it. I keep reading that water should come out by the ball gears. Is there a telltale type thing somewhere there or does it just ooze out? How well can one actually see said water coming out with the boat in the water?

These questions lead me to want to put a flush tee so I have an easier way to check for water flow perhaps even put a pressure gauge such as this on it.



First is there enough pressure in the system to make that worthwhile?
Second I'm not sure where I need to put the tee - 79' 120 model# 990243s

In this hose I believe goes from the transom on the sb side to the exhaust?



Or in one of these on the front of the motor?



On a different subject what RPM should I expect to see @ WOT?

 

[Scott Danforth]

you should have a port on the side of one of the stringer drive bearing caps for flushing. (the one thing I liked about my stringer drive).

your pump will only generate about 19psi and is only flowing about 15-18 GPM. the gauge you have shown will not really be of any use.

generally the impeller is a maintenance item that gets replaced every 5 years in fresh water and about every 2-3 in salt water.

the water comes out the exhaust port (by the ball gears) and is only sealed to the leg when the drive is down (for running). there is about a 2.5" diameter o-ring like gasket that seals this.

 

[TruckDrivingFool]

No port on the cap, I actually just order one of the flush caps off Ebay.

That pic was just the first on that came up when I googled, is there an inexpesive water pressure gauge that could be hooked up to one of these?

I've never actually had the boat on the water since I bought the boat on a 0? Feb day. We ran it dry just to be sure it ran before I bought it. I know not the best way to buy but it's the way it happened. Between that and wanting piece of mind I changed it out.

 

[southkogs]

I've seen Ts put in on the front of the engine as a flush kit. I've never done that with mine. I do have the pivot cap link (painted it this year so it looks much better now):


A Stringer is pretty much under water when you're on the lake, so you'll never really see a telltale. Generally like Scott said, you'll see the water escape under the ball gears, though the pivot caps have a couple of streams that will exit there too ... though, mine has at times looked more like a sieve.

 

[Redrig]

Have you bought the flush cap already ? If not just get a simple Tee and add that on the line that comes from the sterndrive to the thermostat housing (the hose that runs along the starboard topside of engine) only costs a couple of bucks and does the same thing. I have one on mine and it works great.

http://www.amazon.com/Prestone-AF-KI.../dp/B000CCFY5W

also I have noticed on mine that when running off the hose , I will get a stream that comes from the starboard side of the intermediate and streams right onto the ball gears. I dont know if that is on all models , but that is a quick easy way to tell for me that its flowing good.

 

[TruckDrivingFool]

If not just get a simple Tee and add that on the line that comes from the sterndrive to the thermostat housing

I guess this where I ask, isn't the square box thing in the 2nd pic above the Tstat housing? As the hose from the sterndrive goes straight to the exhaust riser as show in the first pic above. There are no cooling hoses running down the SB of the motor and the one pictured above that goes along the port side of the motor by the VC is the fuel line. I did already order the flush cap and it's on its way but I'd still like a way of checking flow for future use.

That said - I took it out today :joyous: and it must be pumping as the manifold never got hot enough that I couldn't put my hand on it. I would like a way to check it though.

Water temp was 70? by the fish finder and the temp gauge never showed above 160? but it's flakey and sometimes takes a few taps to get it working again. The engine itself did get warm enough a couple times that I if touched the head, hoses, or VC I couldn't leave my hand there for long. Does that sound about normal?

Bear with me as I have a few other questions,

I still have to sort out the selectrim (I think it needs the motor replaced/rebuilt) but with trim showing roughly middle I got 32mph @ WOT of 34-3500. Does that sound about right for this boat and what is recommended operating range/max rpm for the 120s?

Is it normal to have a lot of exhaust bubbling up by the ball gears at idle when on the lake?

 

[southkogs]

I still have to sort out the selectrim (I think it needs the motor replaced/rebuilt) but with trim showing roughly middle I got 32mph @ WOT of 34-3500. Does that sound about right for this boat and what is recommended operating range/max rpm for the 120s?

32 sounds okay, but you probably want a little more out of it. I would think WOT would be up around 4000RPM or maybe a little higher.

Is it normal to have a lot of exhaust bubbling up by the ball gears at idle when on the lake?

Yup.

 

[TruckDrivingFool]

Thanks guys, my oem service manual showed up today and now all is clear.

4200-4600 is the WOT operating range so looks like I need to get the selectrim fixed and see where I'm at, may be some room for improvement.

Also figured out on the 120's water is circulated from the SB side to the exhaust where it goes forward through the inside passage (closest to the head) of the manifold to the Tstat then circulates through the motor and exits through the outside passage of the exhaust manifold

Final thought I may grab one of those gauges just grins and see what it reads when attached to the flush cap. may be a way of monitoring wear on the impeller.