I just talked to the preluber vendor on the phone. It turns out that my 10A pump will briefly draws 12-13A when pumping cold thick oil. He suggested to use a 15A fuse. The 15A pump is primarily for large diesel truck engines.
Pre-luber draining battery gives hard cold startup
- Thread starter sifan
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Sifan mentioned two problems he experienced in cold weather: 1. His prelube pump groans and blows fuses and 2. His car is hard to start at -30 degrees F.
My last post was only addressing problem #1. Just from the fact that he could start his car AND run his pump at the same time at -30 degrees F proves that the electrical path from the trunk to the engine bay has very low resistance within an order of magnitude
of what a 2 AWG battery cable would provide. Even if there's 10 gauge wires between the prelube pump controller and +-12V the total voltage drop is still in the tens of millivolts.
I have a trunk-mounted battery in my '95 Saturn with 1.9L DOHC. I've started it in -4 degrees F without problems. I use a 2 gauge cable for both hot and ground.
His car has an even smaller engine - 1.5L. Because we don't know the resistance from the trunk to the engine all I can say is that at -30 the voltage drop problems with two 2 gauge wires are negligible compared with the loss of battery power at such low temperatures
and the high viscosities of the engine fluids. It's probably a good Idea to get a cable for ground because if you are keeping your car for a while the contact points in the chassis may rust.
I recommend cleaning off all your connections to remove all rust. Rust has very high electrical resistance compared with copper and can drop the voltage a lot more than the difference between 2 AWG and 0 AWG.
I would also recommend applying dielectric grease to the terminals to protect the metal from rusting.
To reduce pumping losses in the winter you can run a lighter weight oil.
Honestly I never experience -30F, but single digit F is the lowest winter temp in Maryland. The preluber fuse blew twice at 16F and 22F respectively, both below 32F. I know the preluber still functioned at 30F.
With the help of bypass filter my M1 5w30 oil still has the light honey color after 6k miles. I think I can still go for another few thousand miles before aother full oil change. I am reluctant to change it to M1 0w30 now since weather is getting warmer, and my engine is specified for 5w30 oil. Maybe right before next winter I will try M1 0w30.
I did notice some discoloring on the negative battery clamp and post the other day. The Odyssey battery came with brass battery posts. I thought they would resist rust and need no maintenance. How do you clean them in this case?
With the help of bypass filter my M1 5w30 oil still has the light honey color after 6k miles. I think I can still go for another few thousand miles before aother full oil change. I am reluctant to change it to M1 0w30 now since weather is getting warmer, and my engine is specified for 5w30 oil. Maybe right before next winter I will try M1 0w30.
I did notice some discoloring on the negative battery clamp and post the other day. The Odyssey battery came with brass battery posts. I thought they would resist rust and need no maintenance. How do you clean them in this case?
In my battery relocation project I used the battery cables from Jeg's dual battery kit which means each cable (+ and -) has two battery terminals. Initially I was thinking of installing two batteries (Odyssey and OEM), but later abandoned that bad idea. I insulated the extra terminal on the + cable, but left the one on - cable exposed and rested on top of a J hook with metal to metal contact. Since the J hook attached to the metal battery holder coated with plastic, I thought it was ok to leave it like that. The other day I decided to insulate that exposed - terminal with electrical tape. Wow, it made a big difference. Now the engine starts up with a vengeance. I guess my battery cabling is good after all just a tiny detail was overlooked.
My negative cable lug is bolted to a metal panel in the trunk that is not exposed to outside elements. So, rusting should not be a concern.
I think my pre-luber blowing fuse has nothing to do with battery and its cables. It is just a separate issue. The pre-luber pump has its own behavior. The pump came with a bypass kit that set the bypass pressure at 35 psi. Theoretically it should not blow the fuse if the bypass kit functioned as it was suppose to. Twice under below freezing temp the pump did generate enough oil pressure to turn off the low oil pressure warning indicator, and kept pumping for more than 20 seconds, then the fuse was blown. It seems that the spike of current draw at 12-13A as the vendor suggested came at the very end of pumping session which was kind of odd. Since the winter is getting warmer, it is not likely for me to repeat the situation. I will use a 15A fuse next winter, and see what happen. If the 10A pump motor eventually got damaged due to high electrical current, I would replace it with a 15A pump motor. I guess it is always a good idea to overbuild a bit to avoid nasty surprises, and to save a bit of money in the long run.
My negative cable lug is bolted to a metal panel in the trunk that is not exposed to outside elements. So, rusting should not be a concern.
I think my pre-luber blowing fuse has nothing to do with battery and its cables. It is just a separate issue. The pre-luber pump has its own behavior. The pump came with a bypass kit that set the bypass pressure at 35 psi. Theoretically it should not blow the fuse if the bypass kit functioned as it was suppose to. Twice under below freezing temp the pump did generate enough oil pressure to turn off the low oil pressure warning indicator, and kept pumping for more than 20 seconds, then the fuse was blown. It seems that the spike of current draw at 12-13A as the vendor suggested came at the very end of pumping session which was kind of odd. Since the winter is getting warmer, it is not likely for me to repeat the situation. I will use a 15A fuse next winter, and see what happen. If the 10A pump motor eventually got damaged due to high electrical current, I would replace it with a 15A pump motor. I guess it is always a good idea to overbuild a bit to avoid nasty surprises, and to save a bit of money in the long run.
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I'm glad to hear you helped mitigate the problems.
AFAIK, All metal connectors except stainless steel and rustproof brass rust if they are exposed to oxygen.
I took my own advice yesterday and cleaned all my connectors with a solution of vinegar and salt and a brush. Afterward I applied a copper antiseize paste between connnections to fill the air gaps. Now the lights no longer flicker and the battery charges to a higher voltage. I read somewhere that a fully-charged battery will have an open-circuit voltage close to 13 Volts.
AFAIK, All metal connectors except stainless steel and rustproof brass rust if they are exposed to oxygen.
I took my own advice yesterday and cleaned all my connectors with a solution of vinegar and salt and a brush. Afterward I applied a copper antiseize paste between connnections to fill the air gaps. Now the lights no longer flicker and the battery charges to a higher voltage. I read somewhere that a fully-charged battery will have an open-circuit voltage close to 13 Volts.
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