MG Car Repair: XPEG Tappet Cover & Breather Assembly, fastening bolts, rtv sealant

Question
QUESTION: Hi Barrie,
I'm going back to original tappet cover & breather vs after-market cast Al plate...any tips on how to install...as assembly vs separate pieces ? Pipe orientation ? 3M Blue Sealant ? Seals around 3 fastening bolts ? Had always used the cast Al on TF in past, but decided to go more for preservation.  Not sure what spring bracket is for on original tappet cover either. Sorry for multiple questions but same topic.  You've been big help in recent past.

Thanks in advance / Bill

ANSWER: Hi Bill.  The bracket on the cover plate does nothing on the TF, it is just `there'.  

Use the correct cork seal with drain holes at the bottom, and seal with Hylomar Blue sealant.  Look carefully where the head joins the block.  Sometimes they do not line up correctly, especially if the head has been skimmed.  You may need to use some RTV sealant at the joint.  Do not over-do the amount of RTV.  

I do not recommend the original alloy tappet cover tube nuts - they stretch and fail.  Buy brass ones with O ring seals from Roger Furneaux (Google `Mad Metrics').

---------- FOLLOW-UP ----------

QUESTION: Do you advise assembling the cover & breather 1st, then bolting assembly to engine or cover to engine 1st making sure good  fit & seal then breather afterwards.....difficult "real estate" to deal with when engine in car.  I'm leaning toward #2 approach, but your experience of great value.  Thanks again / Bill

PS Will followup with Roger & Mad Metrics.....

Answer
Before you fit the cover, please check that it is perfectly flat by placing it on a flat surface and going all round it with a .020 feeler gauge.  If it is warped, it will never seal properly.  Use a big hammer and a blunt chisel to flatten it if needed.

The fitting sequence is: (1) glue the gasket to the block and the head, (2) fit the clip to the breather elbow, (3) fit the cover to the car, and (4) fit the pipe to the elbow, turning it until it looks right.  (You cannot get this right when it is off the car)

Finally, (5) attach the bottom bracket between the pipe and the bell housing.