Thread: Another 300 tdi overheat!

I have since found out that even though it is a bare head, the valve guides will be installed. I am going to disassemble my old head and lap the old valves into the new head. Provided I get a good seat (after applying some Prussian blue) and provided the slop between the valves and guides is within spec I will be refitting the old valves as is.

Originally Posted by Matplat

I have since found out that even though it is a bare head, the valve guides will be installed. I am going to disassemble my old head and lap the old valves into the new head. Provided I get a good seat (after applying some Prussian blue) and provided the slop between the valves and guides is within spec I will be refitting the old valves as is.

I think you will wear out your palms trying to lap that way, the seats need to be aligned with the centerline bore of the valve guides, that's why the seating tool is aligned by the valve guide, you will need the proper tools to do it, Regards Frank.

Originally Posted by Tank

I think you will wear out your palms trying to lap that way, the seats need to be aligned with the centerline bore of the valve guides, that's why the seating tool is aligned by the valve guide, you will need the proper tools to do it, Regards Frank.

And best done on something like a Serdi which centres on air and can cut the seats to the exact width and height you want.

It's also easy to throat the port at the same time with another cutter, gaining a little flow

So I went to the machinist and collected the block, crank etc.. Looks a bit different now!! Il post a photo when I'm not on my phone...

I managed to lap the valves into the head, all checked with bearing blue, however it took a while!

So I washed down the block and crank and was commencing assembly... Then I got to the T-seals, I'm not sure what is normal but each seal will need to be compressed approx 1.5mm to allow the cap to get into the block. The seals aren't very soft so getting them in as is seems almost impossible. Does this kind of situation sound normal? Or are the seals wrong? Haynes says to use feeler gauges to guide the seals into the block but they were no use...

Sounds a bout right Matt,
they are pretty tight fit and not overly compressible.

Good to hear you are almost done!

When you say you washed the block, Was it not steam/ pressure cleaned from the builders? Or do you mean you just washed out the pots to remove swarf and machining oil?

With all that rain you guys have at the moment, Id be spraying light oil onto all machined surfaces to prevent flash rust - it can happen in a few days eh.

S

Cheers mate, yeah I'm looking forward to this episode being over, I'd hate to count the number of hours I have spent thinking about it all and stressing over the details, plus the unexpected hiccups...

The block definitely hadnt been steam cleaned, there was still some swarf left on the block, plus as you say grime in the bores, it had been acid dipped though. Went over it thoroughly with hot soapy water then degreaser then compressed air to dry. Finally doused with WD-40 to keep that rust at bay!

Well, just thought I would update everyone as this thread has actually grown to a reasonable size....

I got everything back together over easter after a few hiccups, the most recent being breaking an oil ring while inserting a piston

The battery is shagged to say the least after having spent the best part of 4 months completely discharged, but I managed to get enough juice into it to fire the old girl up. I was pretty happy at that point. Took it for a test drive and the turbo carked it however I was kind of prepared for that to happen as it had been lubricated by water when the engine actually stopped.

What is really getting me now though is that the rear main seal is leaking I ended up giving the t-seals 2 weeks to settle while I waited for new oil rings to arrive so i'm pretty confident in them.

I reckon I am just going to let it leak for a while so bank balances can recover.... I have ordered a new turbo cartridge from e-bay so will let you know how that goes....

Rear main failure is a combination of the T-seals and the rear main seal.
Did you insert the rear main carefully without lubrication using the seal guide?
Was your crank and in particular the rear seal journal linished?

bugger about the turbo

S