Oil Coolers, Worth the money?

[jdaley1847]

Do oil coolers really help keep the engine running cooler on 49cc? Any one have expierence with them on 49cc scooters that are heavily modified?

[Rune 75]

May 8, 2019 22:34:18 GMT -5 jdaley1847 said:

Do oil coolers really help keep the engine running cooler on 49cc? Any one have expierence with them on 49cc scooters that are heavily modified?

I have heard/read that the oil pump on 49cc don't have enough power/capacity to pump oil around a cooler. You might get a cooler engine but you loose oil pressure and that's really bad.

[ThaiGyro]

What a great question! I am nearing "old f*ck" status, where some cannot appreciate what it means to be a Baby Boomer. I won't bore you, so ask your Father...Google.

Here are my thoughts, from early 70's to now experience:

In terms of simple oil reliability/preservation, the answer is to keep it as close to ambient temperature as possible. The lower the temperature, whether from friction or other heat sources, is always better.

It is just not possible...or really, practical. OK, basics.

An air cooled engine, whether 2T or 4T actually runs better when the engine is heated to some dynamic value. No two the exact same, but similar. The reason is cooling, or the lack of it. Engineering of higher or lower standards. It is really all heat and material balance. Heat has a cost, the materials have cost of creation/assembly/repair. That is the simplification.

So, to your questions. Yes, oil coolers are valuable for oil and mechanical reliability. On a modern liquid cooled scooter they may not add value. Some designs of today's scoots have fairly low oil temperatures, because the engine heat fro combustion is being removed.

If you are thinking about it for a 49cc air cooled engine...Do not worry about the pump pressure. If you mount the cooler height properly, there no big load issue, simply more volume, which takes longer to heat and is easier to cool.

I would first get the Air/fuel ratio correct. The heat from combustion is more variable than you would believe.

[lupo76]

They work good on an oil cooler. But if its neccessary, another question...

The Oil pump pumps it trough these radiators, but I recommend to use max 10W40, not 15W40, due to it´s thickness when cold.

[lilpinny]

I looked into them and what i learned is that they don’t really work too well.

[lupo76]

May 9, 2019 8:05:35 GMT -5 lilpinny said:

I looked into them and what i learned is that they don’t really work too well.

Mine do. 

e.g: Sym Mio 50, almost 20.000 on the clock. pump works like a charm... 

another e.g: Chinese 139qmb broken after 9.000, but basically its the same pump between these models. 


Now the big BUT: 

Same pump, but totally different level of tolerance and quality. 
I mean it´s a difference, if you buy a scoot for 650 bucks, or 2000 bucks (converted to USD). 

Hope everybody can follow 

[jdaley1847]

Thanks for all the input, greatly appreciated!

[ThaiGyro]

Here is yet another abstract thought: I recently installed a fancy protective radiator guard on a CRF250. The reason was that the guy was shitting himself every time he had a bad face plant/dirt nutting, resulting in radiator damage.

I tried and tried to teach them (a team) some common sense. The new radiator guard cost nearly as much as a radiator. My advice? Learn and practice how to crash in those conditions, or avoid them.

The analogy? You can spend money and gain nothing...or little...or a lot. Plan your spend, know your desired outcome and study, test, study, test.

The real bottom line is this:  High heat input = more cooling needed.  If your 49cc/70cc/OMGcc engine oil temp is running super high?  You have other issues.  Synthetic oils with low use, do not break down quickly.  Hehe, just change it!  My Gyro holds near nothing.

If you are racing?  Is your scooter in a 6 hour endurance event?  No...cooler not needed.

[aeroxbud]

It's an interesting question.
The way I look at it is these scooters are made to be used all round the world. Sometimes in very hot conditions. Mostly in slow moving city streets. It they cope fine with that, for most a cooler is not needed.
On the other hand if you start to modify something. Possibly making double the original power. It might need a hand.