Block Heaters on the fritz

[Luckyducky]

Does any one recognize these block heaters. Both are bad. Corrosion has set in and when I turn them on at the breaker, I can hear an electrical arcing at the probe. I have JT 671TI in my 1981 37C. The probes are installed just behind what appears to be a fuel pump(not positive). Pictures included.

1) Can I simply remove the fuel pump then remove and reinstall a new probe. Any tricks.
2) is the probe heating the block into antifreeze or oil.
3) If I take the probe out, will It drain out. Do I need to drain the fluids before I try to change the probe.

 

[Luckyducky]

A few more pictures.

Where is the best place to buy replacement parts.

Thanks.....

 

[captddis]

They are Kim hotstart. they can be bought online. They go into the water jacket and the coolant will need to be drained. Yes I just remove the fuel pump for easier access.
When the coolant is refilled the engine needs to be run before using the heaters as air pockets form a nd the elements burn out.

Are the corroded cables the only problem? I have a number unused cables for those heaters.

 

[Luckyducky]

I'm not sure if just replacing the cables will work. When I turn them on, I can hear electrical arcing where the cables attach to the probes. It would be worth a try. Then I'd Replace the probes if mine are to far gone. Can the probes be tested with a multi-meter? If I have to replace the probes where do you drain the antifreeze without dumping it into the bilge. Do I need to pump it out.

 

[Luckyducky]

Could I buy a couple from you

 

[davidwigler]

I have a new pair of cords with thermostats I'll sell for half price.

 

[captddis]

Could I buy a couple from you

You can have two new cords for 20.00. Yes you can ohm out the element, if there is continuity it should be ok. The coolant needs to be drained. If is is not too old I would save it if old then I would dump it. It is a job i hate.

 

[brico]

Since I've drained the coolant in my Starboard engine to work on the H/E cleaning I took advantage of replacing the failed block heater. The one that failed was Zerostart 400W 120V and I ordered a replacement from J&T (together with other parts) the cost for new Zerostart 8600368 http://www.oreillyauto.com/site/c/d..._-1&keyword=engine+heater+-+block+-+universal is $41.49 comes complete as per webpage link and this new one is 1000W 120V.

This is how my original Zerostart 400W 120V looks like and the Port engine one raised the engine block temperature from 46F to 88F in less than 24 hours, in fact it may be even sooner but i measured when I switched on and next morning when i came back. Engine started at idle throttle like it was stopped minutes ago after long run. I imagine that the 1000W will be heating it up in few hours only. I'll have to play with it. I know some people keep them on throughout the winter to heat the engine room, but that is not what I intend on using them for but only to facilitate the engine starting.

I do not think you will need to remove the fuel pump unless the probe is larger that the one on Zerostart 1000W. Definitely not for Zerostart 400W and I made a mockup for 1000W with much longer curved probe and it fit without the fuel pump removal.

 

[Luckyducky]

Hey Captddis
I'll try to pm you about the cords. Thanks for helping out everyone.

 

[Luckyducky]

I will definitely have to remove the fuel pump, not enough room. Where is the best place to drain a 671 TI. Should I use a pump. How many gallons should I expect. Maybe I shod read the book, any shortcuts would be appreciated. I still need to check the probes....
Thanks

 

[brico]

I have DD 6-71 naturally aspirated and I drained 9.5 gallons in total. Most of it at the oil cooler drain (the lowest point), about half gallon at the block heater when I removed it. One pint at exhaust manifold drain, a cup at the thermostat drain. If you have removed the cable plugin from the heater element you should be able to remove it without disturbing the fuel pump.

Try slackening the securing nut from the element to loosen it up and wiggle out with the flange in place. If not like that, remove the flange bolts and play with it. Your cable plugin is quite large so having it off, you have space between the block and the fuel pump.

good luck

 

[steve c]

If you need to remove the fuel pump there are earlier posts listing the cautions. Removing the bolts from the fuel pump requires a special wrench. DD indicates a " J " wrench but I found and old fashioned 1/2 x 9/16 distributer wrench works even better. The fuel lines on my Covingtons were flexible enough so that I did not loosen them. It was also mentioned to place a pan under the pump when removing it to catch the pin. In my case I did this and I did catch the pin and did not have to seach for it inthe bilge. Do be careful per the instructions that come with the heater element to align it so that it does not come in contact with the block.

 

[Luckyducky]

I bought my 37C about a year ago, so I'm still learning my way Round the engine room and motors, 671TI. When I bought the boat, the starboard motor block heater plug and cord was unattached laying in the bilge. I tried to reattach it but there is not enough space between the fuel pump and the probe to reinsert it, that's how I was able to take a picture with it removed. I tried to take the port plug from the probe and there is not enough room so I'm not sure of the circumstances that the starboard plug was off in the bilge. So I'm going to test the starboard probe first, but if corrosion on the out side is an indicator of the inside, looks like I'm going to be draining both motors and replacing the probes.