Revs and oil pressure and rod bearings

[Wreck]

I though I’d start a new thread instead of hi jacking UK Luke’s.

I’ve my 2600 type 4 apart to fix an oil leak and inspection , after 20,000km .

The mains are fine but the rod bearings (Silverline)have wear but only on the piston side . The oil pressure is set to max of 60psi hot ,using a 10W50 syn oil .

I’ve noticed in a recent thread that no one seems to use Silverline rod bearings , so I’ve got a set of KS bearings to try , What are the issues people have had with Silverline rod bearings .

Is 60psi too low for an engine that spins just over 7000 rpm ?

[Vanapplebomb]

For rod bearings, there are other bearings I would use first. It is hard to go wrong with the KS or Mahle bearings. Don’t pass up older NOS bearings as well. I have used some Metal Leve (now part of Mahle) rod bearings. Same with cam bearings. Actually, the cam bearings are pretty cool because they have an internal oil groove, which you don’t see very often. Is it needed?...no, but it is nice to have if you ask me.

In Type 4 engines, the Silverline mains are the ones I prefer. I tried a couple sets of new KS and Mahle bearings, all with the same problems...too small on the OD. The silverlines seemed to be consistently the correct OD for proper fit in the case, particularly the three large crank bearings, which I like to see at 70.00mm-70.01mm. In all honesty, the KS and Mahle bearings had good sized small bearings for the cooling fan side of the crank, but the three large crank bearings were not useable with an OD of 69.98mm-69.99mm...no good if you ask me. Others experiences may be different, but the new type 4 mains from KS and Mahle do not impress me one bit.
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1800 Type 4 Berrien 295

http://www.thesamba.com/vw/forum/viewtopic.php?t=487021

[Ohio Tom]

Whatever brand rod bearings you use, you should always be looking at the material they have for the bearing surface.
Shiny white = Aluminum (not good for any performance engine).
Matt grey finish = oldschool Babbit (much better for performance).


If you are seeing wear on the piston side, I would also be looking at pinging issues, or detonation issues.
Something is causing excessive load on them.

60psi should be plenty for your applicaiton.

[Alstrup]

Also, what rod journal dia ?

[mark tucker]

have the bearings coated, be sure the clearance is right.why the 10-50? might try 10-30 too unless you have a lot of clearance. I like tight clearances and 5-20 syn in my stuff.and I always use coated bearings..well most oarts in my stuff is coated. and yes detonation will for sure do it. also fuel in the oil if you have that issue.
if you need that weight oil for good pressure than you need to find that issue. also I usualy like 10 psi per thou rpm. Im not famiular with type 4 stuff.never messed with them at all. do the rods get full time oiling?or do the mains need grooved? I groove all my bearings leaving about 1/2-3/4" ungrooved, some people like a wide groove, but I like a narrower groove so your not loosing much serface aera.(about .080") be sure it's aligined with the crank holes.and be sure the case gallys are free flowing to& through the bearing's. ( remember I know squat about type 4)

[GARRICK.CLARK]

Wreck.
Can you show me a pic of the shell, I want to compare them with mine from a while back, I just replaced them with new and carried on using the engine. Mine Was polished in the bottom of the shell about 10mm wide and edge to edge.
I guess the most force on big end is at TDC AND BDC

[Wreck]

[King_vw61]

Calico coatings on the rod bearings. Shawn Geers showed me a set in a pro stock engine that saw 9500 rpm, looked brand new after one season on them.
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1961 Ragtop, Autocraft 2783cc for street/strip 10k miles and counting...230.84 HP to the wheels thru Muffler 13.4 to 1 on E85
https://www.instagram.com/king_vw61/?hl=en

[modok]

Use a ball end micrometer to measure the thickness and see how much it's worn.

[GARRICK.CLARK]

Wreck. Yours is similar to mine,but the polishing marks is fully across, edge to edge. That grey line in the middle could be a lowspot
How about for the price of a new set of shells put some engineers blue on the bearing surface, fit the rod to the crank, no oil, rotate the rod once, remove rod and look to see if the journal produces the same mark across the blued bearing
My rods are notched. Wonder if at high revs the notches are working too good.

[UK Luke 72]

Let's not digress down the 'you should run this oil' debate, but what are you running?
Looks like- as Garrick says, the film strength of the oil might be lacking at the points where load is highest.
If you're sure the rods and journals are round.

60 psi sounds fine to me. The fact it's lived happily for 20k km would suggest either the damage was done earlier on when you had tuning issues or ( if they mic up ok) it might just be normal wear for an engine turning 7k rpm on aluminium bearings.
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2276 Beetle build https://www.thesamba.com/vw/forum/viewtopic.php?t=670744&highlight=2276+beetle+daily
2276 EFI Conversion https://www.thesamba.com/vw/forum/viewtopic.php?t=689172

[Wreck]

[UK Luke 72]

I've literally just switched to Penrite
HPR5 though as my cold pressure is a bit higher than I'd like.

I'd be inclined to build it back up with new rod bearings and send it.
I'm almost certain my bearings will have some witness marks on em from when I was having my EFI issues with break-in. All part of the learning curve and it seems to have survived though.
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2276 Beetle build https://www.thesamba.com/vw/forum/viewtopic.php?t=670744&highlight=2276+beetle+daily
2276 EFI Conversion https://www.thesamba.com/vw/forum/viewtopic.php?t=689172

[Wreck]

[UK Luke 72]

People have coated them at home.
Andy198712 did all his dfl, tbc etc, search some of his older threads.
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2276 Beetle build https://www.thesamba.com/vw/forum/viewtopic.php?t=670744&highlight=2276+beetle+daily
2276 EFI Conversion https://www.thesamba.com/vw/forum/viewtopic.php?t=689172

[jpaull]

Luke has a great point regarding the oil film strength. There is no relationship between cheap/expensive/syn/dino/european/USA when it comes to film strength. You might have oil that is $30 a quart and it only has a 50kpsi film strength. Quakerstate syn ultimate dexos 5-30 (green bottle) that can be purchased from walmart for $25 has one of the highest film strengths at 133,000psi. I would run that over your expensive 10-50 syn that let your rod bearings get like that.

If anyone has not read it yet....
When your relaxing and want a long leisurely read:
https://540ratblog.wordpress.com/2013/06/20/motor-oil-wear-test-ranking/

[GARRICK.CLARK]

I'll look into this.
Mine needs an oil change. I use 20/50 in mine, It always sounds better with fresh oil. I've been using 20/50 as a big end bearing cushion, My T4 has the same issue as wrecks does but haven't mentioned it now. I have run mine for years though, I just keep renewing the big end shells . New big end shells fixes the problem, Mileage brings it back. I don't think there's a cure for it .

I'm no oil expert but I take it the oil strength weakens with AGE/HEAT.

This wouldn't be an issue with a N/A mild compression ratio motor. Its got to be
off boost/on boost stressing the bottom radius of the bearing. Add some ping to it and the bearing stress intensifies, add more boost and load/stress at the bearing increases . Before you no it the bearings thinned out at the BDC/TDC position of the bearing. The crank Journals are probably still ok.

[jpaull]

[mark tucker]

coat the bearings!!!! you can do it your self or send them out to be coated. and checl to be sure the rods are round&aligined.

[GARRICK.CLARK]

I'll look out for the high strength oil in the coming weeks. Opie Oils is in UK, they should have a good 1 to try.
Well, just been reading up on it. Any oil over 105k is going to be fine. The zinc needs to be high too
Look at best synthetic oil filter. Com.
167 oils. Best to worst... with all the psi and zinc numbers quoted