Bad weekend (discussion about running bearings)

[Wes M]

I had a pic laying around

It goes all the way thru circled in red, the real question is where does it tee off to the portion circled in yellow

Hi gs,

Its becoming clearer now - After the oil filter the oil runs along a passage located on the left hand side of the block. This is where the pressure switch is located. From there it travels to the area circled in yellow and then up to the oil rail circled in red. So basically the oil feed to the central oil rail comes from the rear of the block. Actually I think Mettler already mentioned this in his post.I like the idea of tee'ing into the oil filter housing and running an extra line to the oil rail through the front of the block. Looks to be relatively straight forward if your not using the aircon (otherwise the ac belt gets in the way).

Incidentally I spoke to another guy today who has run a bearing in a VH (either #5 or 6 he couldn't remember). The impression I got was that it was out of a sedate daily driver which had fueling problems -> bad oil

[Mettler]

Oh sorry I didn't realise I hadn't explained it properly! Yeah if you look at the back of the oil pump housing & filter area, you can see where the oil travels along after the filter in that fat rail on the side of the block, then up that diagonal rail at the back into the center of the motor.

I just went and had a look at the back of the 41... it has a bigger plug in the middle rail, except it is mushroom shaped (i.e. the head flares out and the underside of the head sits flush up against the machined surface on the block), so I'm not sure whether the actual diameter & thread size of the hole is any different. I suspect it's the same.

My guess is the central oil rail is machined from the back of the block!

[SuperHatch]

Now to me, like someone else suggested before, The oil galley bolt for the head does look significantly larger on the back of the block than the front..

As an FYI, those are not the oil passages in the head. Those are casting plugs for the cooling system.

[CrazyTrance]

[QUOTE=SuperHatch]

As an FYI, those are not the oil passages in the head. Those are casting plugs for the cooling system. [/QUOTE

You're right, i was looking at everything again. he diagram doesn't even show oil going through the center of the head like that so i'm not sure where i got that from. I always thought caps for cooling system were a "plug" type cap so in case freezing occured they could pop out and not damage the block/head.

[SuperHatch]

You're right, i was looking at everything again. he diagram doesn't even show oil going through the center of the head like that so i'm not sure where i got that from. I always thought caps for cooling system were a "plug" type cap so in case freezing occured they could pop out and not damage the block/head.

The plugs in the block are exactly as you describe, you can actually see them in the first picture. The head has no such plugs...

[koukimatt]

To fix this problem (on RB’s) is a multi-stage process, but basically you need too:- Fit a larger oil pan/sump- Fit a restrictor in the block & seal up the rear feed to stop as much oil going to the head (RB26 has this as standard)- Mill the oil drains out in the head to the maximum allowed in the gasket- Fit an additional oil drain into the back of the heads.

Can you guys help me identify the openings and passages in the head?



The only one I know for sure is #1 is for a head bolt. The others I'm guessing at:

#2 - oil feed?#3 - oil drain?#4 - oil feed?#5 - oil feed?#6 - water jacket

Where would you put an extra drain for the head?

Where would you put an oil restrictor?
Modified by koukimatt at 10:06 AM 5/3/2009

[SuperHatch]

2, 5, and 6 are all coolant. 1 is a head bolt, just as you said. 3 is an oil drain just as you said.

AFAIK, The head only has two oil feeds, they are the two oblong head bolt areas above and two the right of #6. The oil if fed up and around the shaft of the head bolt. The washer holds the oil in from flooding the head. If you look in those two head bolt holes there are other holes that connect to the oil galley ways, which there are 4 of in the head. Two along the outside edges of the head that feed the cams, and two along the inside that feed the lifters. This method of pumping oil up around the head bolt is a fairly common practice in the import world.

I'm still not sure of what #4 is. It is definitely oil, but I don't know if it is a feed or drain. I would say drain, since there is no need to feed that volume of oil to anything in the head. I'll research a bit more and get back to you.

[Carl H]

the freeze plugs in the above picture above the blue circles look an awful lot like access holes into the head where one could pull the plugs out and it would facilitate a drain.only problem i see with this is that the heads are at 45* to vertical which may prove to be an issue when trying to drain the head...drilled ports near the exhaust ports may be a better option rather than that freeze plug.

[Mettler]

I don't think that's the case! Think about it, they're at the back of the motor against the firewall where you simply couldn't access them.

For draining the water from the engine there are two small fasteners in the sides of the block for that job... with like 14 or 17mm heads IIRC.

[SuperHatch]

I don't think that's the case! Think about it, they're at the back of the motor against the firewall where you simply couldn't access them.

For draining the water from the engine there are two small fasteners in the sides of the block for that job... with like 14 or 17mm heads IIRC.

They're 14mm. the one on the RH side of the motor is more towards the front of the block, the LH side is more towards the rear.

Those massive plugs should never need to be removed.

[koukimatt]

The GM Powertrain guys were dealing with oil problems very similar to these while designing the LS1. Check out this link; search or scroll down to "Oiling System Snag".

http://www.idavette.net/hib/ls1c.html

Maybe the ultimate solution to engine oil problems is a dry sump.
Modified by koukimatt at 9:22 PM 5/8/2009

[Orphan]

Here is a random question not really related to the bearings but why does the girdle not have a cross beam between the rear 4 cylinders? Doesn't really make much sense to me as the rest do and there doesn't appear to be any reason for it not to.

[Mettler]

Hmmm... the main bearing beam is there for the purpose of reducing NVH output, perhaps they achieved some kind of optimal values with it designed that way?

[Aussie Z]

Had a talk with a bloke i know at a local performance shop about this issue and said that all of the holden 6 cly engines have this problem, and all he does to fix it is install an AN fitting to the back of the rocker cover with a drain/return line plumbed straight back to the sump, so that, 1) they cant fill if your lines are big enough and 2) under heavy acceleration all the oil is thrown there anyways and instead of just sloping around it flows straight out the drain.

just a thought

[Mettler]

Here is a random question not really related to the bearings but why does the girdle not have a cross beam between the rear 4 cylinders? Doesn't really make much sense to me as the rest do and there doesn't appear to be any reason for it not to.

I just saw this question again after ages ago, and realised it's because that's where the oil pickup passes through. A cross beam there would interfere.

[darinz]

Here is a random question not really related to the bearings but why does the girdle not have a cross beam between the rear 4 cylinders? Doesn't really make much sense to me as the rest do and there doesn't appear to be any reason for it not to.

I just saw this question again after ages ago, and realised it's because that's where the oil pickup passes through. A cross beam there would interfere.

I knew you fullas from the Waikato were slow, but that is ridiculous!

[holeset]

i dont know if anyone else has found this but i got both cranks out of our two stuffed vh45s and the cranks were bent 30" and 18"!!!!!,now to grind these 10"under would be kinda impossible,my engine grinder crank buddy reckons he can get Heat Treatments to stress relieve the cranks and hopefully pull them straight again to enable a grind and cleanup,anyone else have a similar problem from spun bearings? Heat Treatments reckon they have had alot of these to stress relieve,they told me its due to the heat generated from the spun bearings.

[Mettler]

Well if you're screwed mate, I have a VH41DE crank + pistons spare if you end up with no other options.

[darinz]

There's a crank, rods and pistons on Trademe at the moment but it has spun a bearing as well. The guy wants $150 for it.