Changing the fluids in a 1925

[Guest Leeroy]

Hi guys,

So I've bought the Maxwell 1925 and now at some stage want to drop all the fluids, as I have no idea when it was last done.

 

Below is what I've found, but was wondering what other are using, or what's best to use?

 

I found Penrite Shelsley Range for the engine, comes in light 20-60W / Medium 20-70W / Heavy 40-70W.
I presume after reading the descriptions of each I'd use the light?

For the Gearbox, Penrite also have "Gear Box Oil GB30 and GB40"

And for the Diff - Penrite Transoil 90 / 140 /250.

 

Radiator - I know is water, but with what additive? Soluble oil?

 

[Carsnz123]

Some advice from NZ

 

Engine:

I'd run flushing oil through a couple time first to remove the worst of built up crud. I've had good results with Morris Golden Film flushing oil. As far as main oil 20w50 or 20w60 works well. I've had run of the mill 20w50 in a '29 Plymouth for ages with no adverse effects. At work we use Castrol GTX in all the old stuff. 

 

Gearbox: 

You'd have to look in a manual or ask a Maxwell nut but some old cars use engine oil in the transmission. Otherwise I've had good results with straight SAE90 gear oil (golden film again). 80/90 EPX also works well. Don't be tempted to go too thick or you'll have trouble shifting gears. I've got SAE250 in a transmission and it is a bastard to shift in the cold but it doesn't leak out the 90 year old seals. 

 

Diff:

Pretty much same as trans. If you want to go really fancy Redline sell great "Shock proof" oil which will smooth out even the lumpiest diff. I've got Penrite 75w90 semi-synthetic in the Plymouth diff which I just rebuilt and it's smooth as a fancy gold watch. 

 

Coolant:

step one run flusher through it a couple times to clear it out. I've had good results with castrol radicool and nulon long life coolant (green stuff). I've heard stories of prestone causing excessive corrosion but don't quote me on that. If you don't want antifreese, penrite sell a corrosion inhibitor mix. I was given a bottle on a VCC run but yet to try it.Just remember antifreese searches for gaps. If the car hasn't had antifreese leaks might show up if you start using it.     

[C Carl]

Unknown engine : start at square one. Before you put anything in it , you MUST drop the pan and clean completely. Make sure the oil pump pickup is clean . This is the time to examine your bearings. Pull at least two rod caps and one main cap. Examine and plastigage to verify that the clearances are within spec. If those are good , put it all back together. If they are so-so , but might go , pull the rest. If you find them tolerable , use the VERY BEST OIL YOU CAN POSSIBLY GET REGARDLESS OF COST. If they are questionable , seek expert advice. Ignoring this step can lead to very expensive, time consuming repairs. Haste makes..... oh , you know. Or a stitch in time..........

 

I dont care that the worst oil today is better than the best oil 90 years ago. I don't put the worst oil in my cars. Not even in my 90+ year old cars. Would you ? How about the best ? Sounds right to me. The best is full synthetic. Penrite make a very good line of full synthetic. Go for their 20W/50 , depending on what your bearings tell you. Transmission : as '123 says , consult with tha Maxwell guys. I can give you a comprehensive tutorial on Synthetic gear oils , but I would like for you to get the Maxwell specific info first.  Generally the diff in these ancient cars should carry at least a 250 synthetic gear oil. Some guys use a heavier semi-fluid grease. See what Penrite has in synthetic gear oil , and use at least 250. And speaking of semi-fluid grease , I use Penrite steering box lube. Use nothing but synthetic grease for all fittings. Proper lubing at prescribed intervals with synthetic grease can keep your chassis forever young. 

 

Please let us know what the Maxwell guys say. Non synchro transmissions have very idiosyncratic shifting needs. Some shift better cold , some hot , some have their sweet spot somewhere in between. You have to design the viscosity accordingly. Trick blendings with a base viscosity , eg. , synthetic  250 , and perhaps synthetic grease , or a V.I. improver such as STP blended in , can make double clutching (do you know how ? You must do so on these old crashboxes. It is fun to master the technique) , easier. I am curious what the Maxwell guys will say.  - Carl

[hidden_hunter]

Another vote for Penrite, they make a good product, I ordered a couple of bottles for when I reassemble the cad and there was a bit of a wait on the gearbox oil.

[Carsnz123]

25 minutes ago, C Carl said:

And speaking of semi-fluid grease , I use Penrite steering box lube.

 

Forgot to mention this. bloody good stuff. Doesn't leak out like oil but lubes better than grease and doesn't go rock hard in cold weather. 

[Vintageben]

Yeah Penrite has some great product I have two 1927 Chevs that we drive resonably hard say cruise around the 50 mph speed I run the Shelsley medium in the engine. We use to have a few engine issues but have very few now running this oil it is very tacky oil and works great on the rocker gear as well that only has a felt to keep the oil there. As for the gearbox and diff I'm running from memory a straight SAE 140 and have had no dramas with shifting at any temp oh sorry I live on the NSW northcoast Australia so it doesn't see snow or anything that extreme. Penrite also does a good water pump grease as well. Back to the engine oil I like the tacky oil as some times when that four letter w word gets in the road we

might not drive the cars for a month or two but things stay coated and also think it works well with the primitive splash feed system the Chevs have. Any way just a few thoughts the main thing is drive the car and enjoy it and you will learn a lot along the way.

[Spinneyhill]

I would think the car manual originally called for an engine oil more or less equivalent to SAE 30 (such ratings only came into use in about 1924 or 5).

 

20W sounds thick for startup. To get lubrication quickly, a smaller number before the W is better, e.g. 10W.

 

I don't know why people specify SAE 50, 60 and 70 oil for old cars. In my opinion it is far too thick. In the absence of any other information, I would try 10W-40. If the engine is worn (compression, plasti-gauge on bearings as above?) maybe a 10W or 15W-50.

Edited June 20, 2017 by Spinneyhill (see edit history)

[maok]

I use Penrite T250 for the trans and diff. Its very think, almost like honey. If you overfill, it will take longer to get to operating temp. and gear changes will very stiff and crunch, especially from 1st to 2nd.

 

The Penrite water pump grease is excellent. Its more like a wax structure than grease.

[Ron Lawson]

Head CAUTION in the transmission and the differential as modern oils contain additives that EAT away bronze bushes and gears Penrite make oils that are "yellow metal" friendly 

[Guest Leeroy]

Thanks guys, I'll stick with the Penrite.

[Spinneyhill]

SOME EP additives attack copper and thus yellow metals. You CAN use EP oils IF AND ONLY IF they pass the copper strip corrosion test with a 1A and 2A result.

 

See post #322 and around on. p.13:

Look for the copper strip corrosion test results for your proposed oil. If you can't find it, look for another oil.