L28 Problems opinions needed.

[24OUNZ]

Hi guys,

 

Apologies Ive been learning a heap on the website of recent times so please be gentle….. I'm no mechanic so i may get the wording wrong...

 

Ive been looking everywhere around the net for resources on this and just wanted everyones 2 cents worth.

 

I have a L28 with N42 head and F54 block. The motor was running fantastic recently till white smoke started to blow continuously from the rear end with occasional puff of blue smoke. So the usual culprit …….head gasket..??

 

Pulled the head off to inspect the gasket and start on a refresh of the head etc. But before i go ahead with it or decide to pull her out and rebuild her i wanted your opinions. Her are some photos of her.

 

 

No tears in it i can see

 

 

 

 

 

3rd cylinder with coolant and "sludge" in it sorry for the bad photo.

 

I have had coolant getting into the 3rd cylinder (indicated by the clean pistons 3rd and 4th cyl compared to the others)  and that was indicated on the CR test i ran on her (see last photo of inside 3rd cylinder). She was down to 105 compared to the others at 120+ and i noticed that in the week leading up to it blowing smoke, i did start go through coolant but there was no white smoke to be noticed at that stage.

 

Also i wanted to see what everyone thought of the "yellow sludge/gunk" that seems to be around the back water jacket/gallery and in the various ports on the block and head gasket…. is this common and is it corrosion??? My thermostat housing has the sludge in it too but the thermostat itself was clean as a whistle.. Of course it sounds like I'm going to need to do a flush of all the coolant system which i was planning anyway.

 

So if the head gasket wasn't the problem what could be causing the above problems….

 

Apologies for the wording of my post I'm no mechanic….. Thanks for your time and help and valued info.

 

Al

 

 

 

 

[ZED83]

Sounds like a head gasket to me. The sludge is "oil" mixed with coolant. I'd replace gasket with a metal head gasket. Not saying you should but that's what I would do.

[Linton]

I would agree with you 3&4 as the culprit you can see it on the head gasket. previous post mentioned oil mixed with the coolant = sludge, now that the head is off I would lap the valves and throw a new set of valve stem seals in. Crazy not to you have already done most of the work

Linton

[dat2kman]

Is it my crap eyesight, or does that head gasket look like it is not allowing some of the water passages in the block, to flow up and into the head?

For a basic build engine save yourself the expense of a metal head gadket (MLS) just use a common popular type, ie ProTorque etc.

Ceratianly give it a clean up, and a few thou skim off the face to true it up.

The crud in the water passages in the head, is an indication of what is also in the block.

Any pissibility of stripping it down?

At minimum,, a fresh set of bearings, a full gasket kit, and fresh rings, on the old pistons, and give the bores a flexhone.

[oldmates260z]

Always remember things fail for a reason, if the head gasket failed, ask why?

 

You will need to ensure that the head is not warped at all. Did it overheat at all? Are you sure the temperature gauges is working properly? Can you tell where the water was tracking through the head gasket? You need to be sure that just a head gasket will fix the long term issue.

 

May be you could get the head done up while its off, skim and new valve guides (if you have the money)

 

I would be concerned if there are any blocked water journals, these need to be flushed out plus the radiator

[24OUNZ]

Thank you all for your input and suggestions.

 

I was wondering the same if the water journals were being blocked as well from the gasket and it appears they are blocked on the block as well.

 

Any good suggestions I how to clean the journals and general clean up of this oil coolant sludge mix in the block and journals?? Ive never done this before.

 

As for the head defiantly will be getting it cleaned skimmed valve stem seals done and maybe the valve guides. I'll see how much it comes to. And of course a pressure test to check for cracks or warping. And a head gasket done.

 

Any further suggestions??

 

Thanks all for your help!

 

[dat2kman]

Full diss-asseble, and hot tank clean.

Remove oil gallery plugs, and rod clean the galleries/feeds etc.

[dazzed]

Full diss-asseble, and hot tank clean.

Remove oil gallery plugs, and rod clean the galleries/feeds etc.

And if you dont do all of the above you will find it difficult retiming the cam when the piston is way past top dead centre,

[Riceburner]

+1 full disassembly. With the correct manuals and correct tooling you can reassemble yourself.

 

Piston #3 is steam cleaned 

 

I recommend a good coating of 'hylomar' on any head gasket before install, it's never failed us. I currently have a 'mismatched' block head combo on my L28 blocking water galleries, not ideal. So far with the Nissan 89mm OEM gasket, 'hylomar' coating and ARP head studs I have had zero issues at extreme conditions on track/road. That's with an LD28 water pump (much more flow/pressure) and a 'D.L Potter' water restrictor now NLA.

 

ARP head studs are not much more than new OEM head bolts from Nissan and It's a no brainer.

 

How much of this can you realistically do yourself and what tools do you have?

 

Peter Mc did an excellent job for me at a very good price. His expert help years later has been invaluable.

[24OUNZ]

Well looks like a full disassemble it is!

 

I've got the correct manual and all tooling just got to purchase the new parts (bearings, rings etc)

 

I think I might as well just do a full rebuild the way it's going....

 

Thank you all for you help. Hope I can get her back on the road soon!

 

Cheers

 

Al

[pauly_adams]

personally I would just skim the head and put on a new gasket, if it lasts great if not give her a rebuild