L24E Water in Oil Problem

[wardie]

Hi All, I have a MR30 Hatch with the L24E motor and she died on me near work a couple of weeks ago (till then a good motor). Radiator was empty and the oil was like milk chocolate. I pulled the head off and got it tested (Ok I was told). Refitted the head with an new gasket kit and the same thing happened straight away (30Km) . Head is now back with the mob that did the pressure test previously as a mechanic at work reckons that these motors do heads. Can any one confirm this? Is there a chance that the block has cracked or other problems. It has been suggested that the water pump/cam chain housing may be cracked and letting the water into the oil.

[machg]

Heads on these engines are prone to corrosion, and finding good heads for L series engines is getting very difficult and therefore expensive, however you can't assume that this could be the only cause of your problem..

machg

[66 skyline gt]

i had the same problem with my head on my L28 in my 66 gt...... Solution....... I droped an rb20 det in the cvar because the head that i was after are like rockin horse poo...blood hard to find.

see if ya cant find a cheap complete motor out off another early skyline, or even a recon job.... might be cheaper in the long run

[V8skylineMAN]

hmm...could be the block but not likely.......water pump/camchain housing....very possible...i would check that for sure........ its much cheaper than the rb... or reco avenue....

[wardie]

Thanks All, Have been away and will have to chase up the head tomorrow. Definitely will pull the water pump out and check that area out for corrosion on the weekend. I hope its not too terminal as I like this car, went well for the cost.

[wardie]

Hi All, got the results of the head re-test. NOT Cracked or Warped. Have not been able to get the time to get the timing chain cover off, no puller for the crank pulley yet, but the shop that has done the head re-test suggested that there is a welch plug in the block under that cover. Anyone know if this is right, seems strange to me as I am used to welch plugs exiting to the outside of the engine? Any advice will be gladly taken as wife wants her car back. Thanks, Wardie

[V8skylineMAN]

Yes, there is a welsh plug in the block behind the timing chain cover....

[wardie]

Thanks, V8skylineMAN. Off to the tool shop for a puller tomorrow then. Dumb place for a welch plug!! Do you know if the welch plugs are standar size or do I have to get them from Nissan?

[V8skylineMAN]

its been a while, so i dont remember...but the parts shop should have them....i tend to think that they are standard size, but just get them to check in their books

[Duncan]

yeah Welsh plugs are a couple of standard sizes....but I don't know which one you;ll need. Places like Supercheap stock them

[SteveL]

It'll be either 30mm or 35mm - I think 35mm from memory, I can double check on a spare block if you like. Get any replacements in brass, not steel (which is what the factory ones are made of. Check the other welch plugs for tell-tale rust trails - unusual for just the front one to go.

Did you check the head for corrosion damage at the water transfer passages ??

Also removing the front cover requires breaking the sump seal.

[V8skylineMAN]

Also removing the front cover requires breaking the sump seal.

Yeah, thats right. nothings ever easy is it?

who in their right mind would work on a car?

I would. But I'm not in my right mind, either.

[wardie]

Finally got the timing cover off after breaking two bolts in the harmonic balancer. Looked at the welch plug and it seems to be intact. No evidence of corrosion at all. The outside face looks as new. I am now thinking that I have some corrosion in the block that has made it's way through to an oil passage. If so I think I'll be up for a second hand block/motor. Anyone with any hints as to availabilty/cost for a usable unit. Wife does not want me to spend too much time or money on it (actually she said "take the piece of s**t to the dump"). Not asking for freebies just some good advice. Thanks

Wardie

[SteveL]

It would be (very) unusual for corrosion in an L-series block to penetrate an oil passage. If corrosion is a problem, then damage to the head would occur well before it became a problem with the block. I notice they crack checked the head, but was the head checked for corrosion damage ?? A lot of info about the cause can also be gained by examining the head gasket from the original failure (probably not possible now). In particular, the transfer passages at the back of the head (cyl 6) can be problematic if coolant is neglected/not used.

The thing to do is to inspect the head for corrosion damage to the transfer passages and carefully overlay the headgasket on the head to see if there are any 'problem areas' - use the block dowels to get the alignment right.

[wardie]

There was a small area of corrosion damage on the face of the head that was welded up and machined initially but this was towards the front around cylinders one and two near the inlet ports. I do not have the head at this time as I told the head shop not to put it back together until I checked the welch plug. Do you know exactly where I should look as I can go down there tomorrow to inspect it. The head shop has not suggested that there is any other corrosion damage.

[SteveL]

It's really a case of closely checking all the transfer passages, but particularly those where water/oil passages are close together (eg back of the block - the main oil drain).

[wardie]

Thanks, I'll do that.

[wardie]

Woo Hoo!!! Finally found time to take timing cover to the head reconditioner (bloody new job ) as he was insisting that the head is ok and as the welch plug was intact it had to be the water pump area. I could not see any thing wrong but when he put a light background behind the cover there it was, a pin hole in the top back of the water pump area. He's welding it up now and I'll have the head and cover back on Monday.

[V8skylineMAN]

good to hear. glad you found it and it wasnt to major a job to fix.