Recent Posts

1

Chatter / Re: Engine oil in coolant :(

« Last post by knighty on July 26, 2025, 02:50:52 AM »

no experience with your car, but had oil coolers go on work vans before

unless head gaskets are a common thing on those I think the oil cooler is much more likely

2

Chatter / Engine oil in coolant :(

« Last post by Vijay on July 23, 2025, 05:57:24 PM »

Hey guys,

On my Skoda Octavia 1.9. Found some engine oil in my coolant expansion tank last week and been flushing the system out. There's a slight layer of "mayo" around the inside of the coolant expansion tank which I'll need to clean out. Read online to use dishwasher powder and simple green, so will give that a try. Engine oil looks like oil, no signs of mayo in that.


I'm assuming head gasket but a friend mentioned it could be the oil cooler. I just wondered if anyone has ever come across an issue with the oil cooler?

Any other suggestions?

Cheers



Vijay

3

Chemistry and process / Re: Help! Reaction not happening.

« Last post by Sonex on July 19, 2025, 06:08:36 PM »

Thanks for the suggestion.  I just ordered a couple gallons of glycerine to use as you have suggested.  I'm curious myself to see if it has any effect.

4

Chemistry and process / Re: Help! Reaction not happening.

« Last post by dgs on July 18, 2025, 10:48:37 AM »

Any idea how to get glycerol if I'm out of it?

Sorry, no. Thats why I mentioned the glycerol that you washed the oil with, not ideal but better than nothing. You can use pure glycerine but it is expensive here in the UK, i don't know about the States.

Anyone make bio who is close to you to help you out.

5

Chemistry and process / Re: Help! Reaction not happening.

« Last post by Sonex on July 18, 2025, 02:53:40 AM »

Any idea how to get glycerol if I'm out of it?

6

Chemistry and process / Re: Help! Reaction not happening.

« Last post by dgs on July 17, 2025, 05:02:07 PM »

The last time this problem came up, I ended up throwing out the whole batch and starting over.   

It's about a 35 gallon batch of oil.  I poured left over glycerin from a previous batch in it and let it settle out and drain off before mixing in about 6 gallons of methanol with approx 50 oz of KOH dissolved in it.

Does anyone know of a university lab, which would analyze a sample of what I have?

Don't throw the batch away, there will be plenty to salvage. i don't know why this has happened but I'm sure you will have had a reaction.

so....heat up your batch and add what glycerol you have (even the stuff you used to pre treat it with) when it cools you will have a layer of glycerol with bio on the top.

Do you know how to do a 10/90 dropout test.

7

Chemistry and process / Re: Help! Reaction not happening.

« Last post by Sonex on July 14, 2025, 02:20:18 AM »

The last time this problem came up, I ended up throwing out the whole batch and starting over.   

It's about a 35 gallon batch of oil.  I poured left over glycerin from a previous batch in it and let it settle out and drain off before mixing in about 6 gallons of methanol with approx 50 oz of KOH dissolved in it.

Does anyone know of a university lab, which would analyze a sample of what I have?

8

Chemistry and process / Re: Help! Reaction not happening.

« Last post by neisel on July 13, 2025, 01:14:07 PM »

"I've had this problem come up again.."

How did you fix the problem when it happened before?

Please include the quantities of chemicals, WVO etc you used. It might be helpful for those who understand chemistry.

9

Chemistry and process / Help! Reaction not happening.

« Last post by Sonex on July 13, 2025, 12:44:23 PM »

Having made biodiesel for years, I've had this problem come up again.  The oil titrated at about 4.  I mixed KOH in the methanol until it dissolved.  The mixture then got mixed into the heated up oil.  I stirred it up.  A couple hours later, I came to drain out the glycerin, but there was none.  No reaction took place.  WTF?

Could the oil contain cleaning agents, which stymie the reaction?  What should I do with this bad batch?

10

Chatter / Re: Meth

« Last post by dgs on July 09, 2025, 08:50:14 AM »

Can you recommend what to purchase?
Don't want to mess that up as well.

Looked on ebay and can't seem to find exactly the correct one. It has to be accurate in the correct range.

Virgin merhanol has a specific gravity of 0.79 so any water contamination increases that figure. I'll look at the wiki and see if there is any info.