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Author Topic: MTDI in a boat  (Read 9086 times)

Reply #75August 19, 2017, 12:22:30 am

LabradorSteak

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Re: MTDI in a boat
« Reply #75 on: August 19, 2017, 12:22:30 am »
I couldn't find any sensors in the head...I may have removed them all.  I did find the brown one in the side of the oil pump.  If I can find a sending unit that will fit in there I will use it. 

I also found a valve cover gasket leak that I need to fix so before I make too much of a mess I am going to replace that too.  Do people every add a dab of silicone gasket sealer on the valve cover gaskets? 

Matt.
« Last Edit: August 19, 2017, 12:24:42 am by LabradorSteak »

Reply #76August 19, 2017, 03:08:34 am

vanbcguy

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Re: MTDI in a boat
« Reply #76 on: August 19, 2017, 03:08:34 am »
Ok, 20 seconds in that seems like a totally healthy engine. Run her for a few minutes at 2K+ then shoot the same video. I'm figuring you'll have no smoke and a pretty nice sounding engine.

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Bryn

1994 Jetta - AHU M-TDI - Jezebel Jetta
2004 Jetta Wagon - 1.8T - Blitzen

Reply #77August 19, 2017, 11:07:14 pm

ORCoaster

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Re: MTDI in a boat
« Reply #77 on: August 19, 2017, 11:07:14 pm »
dabs of sealant I use are at the ends of the U shaped gasket going over the cam.  Just doesn't seem to pinch it right down next to the cover.
Now Own 1981 Caddy as the NEW DISTRACTION to all that is around me.  Project Away!

Reply #78August 25, 2017, 06:56:47 pm

LabradorSteak

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Re: MTDI in a boat
« Reply #78 on: August 25, 2017, 06:56:47 pm »
How do I know what level to fill my coolant. Can I just have a small tank above everything and have the entire system full or is there a correct amount to have in the engine?

Matt

Reply #79August 25, 2017, 09:49:45 pm

vanbcguy

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Re: MTDI in a boat
« Reply #79 on: August 25, 2017, 09:49:45 pm »
Just needs to be enough to completely fill the engine and leave no air bubbles, plus enough to fill whatever heat exchanger you are using. There's not going to be an "amount" in your scenario.

Ideally you should have an expansion tank, perhaps even a VW one, mounted above everything in your system and plumbed in like stock - there should be a small line coming from the top of the head to the expansion tank (this provides a path for air to exit the system) and a line from the bottom of the expansion tank to the return side of the cooling system.

Fill the system via the expansion tank until the expansion tank is half full - with a sealed system you want the little bit of air in there to deal with expansion and contraction but you want it away from the engine / heat exchanger. Air bubbles circulating through the system can reduce cooling capacity by as much as 30%.

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Bryn

1994 Jetta - AHU M-TDI - Jezebel Jetta
2004 Jetta Wagon - 1.8T - Blitzen

Reply #80August 25, 2017, 11:40:14 pm

LabradorSteak

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Re: MTDI in a boat
« Reply #80 on: August 25, 2017, 11:40:14 pm »
That is the way that I have it plumbed so I feel better.  I just didn't know if it was possible to over fill the system since it really doesn't have an escape valve like on the top of a gas engine radiator.

Is the system supposed to be under pressure?  How hot do these engines usually run?

Matt.

Reply #81August 26, 2017, 12:00:29 am

ORCoaster

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Re: MTDI in a boat
« Reply #81 on: August 26, 2017, 12:00:29 am »
There will be some pressure from the increase in water temperature but I never noticed a lot if I opened the reserve tank once the engine was hot and running.  I think most of these have an 86 degree C thermostat in them.  Mine has a bit hotter but I don't see much above 90 on the gauges.  90 C = 194 F.
Now Own 1981 Caddy as the NEW DISTRACTION to all that is around me.  Project Away!

Reply #82August 26, 2017, 04:56:12 am

vanbcguy

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Re: MTDI in a boat
« Reply #82 on: August 26, 2017, 04:56:12 am »
The cap on the VW expansion tank is a pressure relief cap, it pops around 22-25 PSI.

Temperature wise hot is good. Detonation isn't a concern so you're looking to remove as little heat from combustion that could be pushing a piston as possible. That means hotter coolant temps if you're coming from a gasser world. 90-110C is pretty normal.

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« Last Edit: August 26, 2017, 04:59:32 am by vanbcguy »
Bryn

1994 Jetta - AHU M-TDI - Jezebel Jetta
2004 Jetta Wagon - 1.8T - Blitzen

Reply #83September 12, 2017, 12:05:57 am

LabradorSteak

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Re: MTDI in a boat
« Reply #83 on: September 12, 2017, 12:05:57 am »
Engine is in the boat but I am redoing the engine mounts so when I get that done I will post some pictures.  Next I need to set up the fuel tanks.  I have some old aluminum boat tanks that I am going to use but they have been sitting in the yard for a few years and have some dust and debris in them.  I can only clean them a little since the openings are rather small and the tanks are long rhomboids that don't allow me to see the entire interior much less reach it. 

My question is how should I keep the dirt out of the fuel pump.  Would a couple of filters on each line be enough or do I need to do more...If I should do more what should I do?

Thanks again, Matt.

Reply #84September 12, 2017, 12:27:20 am

ORCoaster

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Re: MTDI in a boat
« Reply #84 on: September 12, 2017, 12:27:20 am »
I would use clear inline filters and replace them often until you are confident that most of the junk is out of the tanks.  Maybe after 3 tank fulls have been pulled through the lines.  The cheap gas filters should do the trick. 
Now Own 1981 Caddy as the NEW DISTRACTION to all that is around me.  Project Away!

Reply #85September 12, 2017, 02:40:27 am

vanbcguy

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Re: MTDI in a boat
« Reply #85 on: September 12, 2017, 02:40:27 am »
A permanent solution would be to rig up some spin-on style filters that you can change easily. Something with a water block media ideally.

A Racor style marine filter with a big water separator would be pretty stellar.

Marine fuel is often dodgy by nature plus you're using more of it than someone would in a car. Spending a little extra money on your filtration setup would be a good move.

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Bryn

1994 Jetta - AHU M-TDI - Jezebel Jetta
2004 Jetta Wagon - 1.8T - Blitzen

Reply #86September 12, 2017, 11:12:00 pm

ORCoaster

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Re: MTDI in a boat
« Reply #86 on: September 12, 2017, 11:12:00 pm »
I was assuming he would be setting something up for the normal filtration process but was looking for some additional filtering for catching the debris in the tanks that might not clean out.

I put one of those Racor filters on my Rabbit when I set up the waste veg oil on it.  I really liked the self priming pump on it.  I still have the base and an unused filter if you don't have something yet I might be convinced to part with it.  PM if you want to deal on it.  I removed the WVO system from the car a month or so ago as I am working on selling it and didn't see where in this day of low diesel prices it would be a big selling point.  I will sell the system on the side when diesel jumps back near 4.50 a gallon.  Or use it on my Caddy.


Now Own 1981 Caddy as the NEW DISTRACTION to all that is around me.  Project Away!

Reply #87May 28, 2018, 12:10:59 am

LabradorSteak

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Re: MTDI in a boat
« Reply #87 on: May 28, 2018, 12:10:59 am »
I have the motor in the boat and I am about ready to try it out in the river.  Unfortunately I have an exhaust leak that will probably end up being a big pain.  My concern is that there is a liquid coming out of the leak.  It looks like oil but I dont know if it is dirty fuel or oil.  I cant tell.  I thought I could smell the difference but it wasnt obvious.  I made a couple of videos hoping that you guys could tell me if I need to rebuild the head or if it is normal for excess liquid fuel to go out the exhaust when the engine is cold.

Here are the videos.  Ask any questions and I will do my best to answer them and will make more videos if it helps.  You can see the liquid moving sideways from the exhaust and running down the side of the head.  One video is directly after starting the motor and one is after about thirty seconds of idling. 

https://www.youtube.com/watch?v=MArMrguJOfE

https://www.youtube.com/watch?v=GdXDYOHqayg

After watching them I realize that they look much, much worse that I thought so I can redo them tomorrow.  You can still see the black liquid coming out the side.

My concern is that the head is cracked and allowing oil to enter the exhaust port although it could also be a leaky valve guide.

Thanks, Matt.

Reply #88May 28, 2018, 12:29:33 am

LabradorSteak

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Re: MTDI in a boat
« Reply #88 on: May 28, 2018, 12:29:33 am »
I forgot to mention that the engine was cold and I dont have glow plugs connected.

Matt.

Reply #89May 29, 2018, 12:59:47 am

LabradorSteak

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Re: MTDI in a boat
« Reply #89 on: May 29, 2018, 12:59:47 am »
I pulled the exhaust manifold and looked closer.  I realized that the egt's werent above 200 and the engine had been running for less than a minute.  I am guessing that is is unburned fuel and all I need to do is seal the manifold to the head better and ignore it. 

If anyone has any input I would like to hear it but as for now I am not going to worry.  If the head is cracked or the valve guides leak then it is what it is already.

Thanks, Matt

 

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