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MG Midget and Sprite General - Black hole saga continues

Hey guys,

Well I hadnt intended to post this because i didnt think it to serious, but because I hi jacked another thread that generated some response I figured I should shed some light


yesterday I decide to run in the cam and get the car sorted out,,,,But I had an isssue with high oil pressure.

In the next posting ill detail out what happened and what I think is the issue and what ill try next

So that said, If the block is cracked, I dont think it will be a big issue, Im guessing Ill just need a another block, machine work, gasket kit, lifters, and piston rings ....the great thing is all the parts have only 3 minutes on them...And all the BS of making high performance parts fit is done, and I figured out how to pull and re-install the datsun tranny super easy in under 20 minutes, So If a rebuild is needed it wont take long...maybe a week at that...And yes Ill even number the plug wires correctly this time...So the idea of doing another rebuild isnt all that disturbing to me....MAYbe to you guys ...ROFLMAO....Hahaha

BUT...I still got 3 cards left to play...and one of them is a wild ace of spades, So this engine isnt dead yet.

1st card...New oil pressure valve was stuck wide open and is 1/2 inch longer then orginal.

2nd card....Remember that discussion 4 weeks ago about the missing oil restrictor in the crank shaft....maybe it needs one

3rd...My Ace of spades wild card...I really am thinking this is the issue....I Revamped the EVAC system and Im getting back pressure from the muffler.and not allowing the PCV valve to open and suck the pressure out of the engine...more on next post

okay there is a forth...the bock cracked during that brutal cold snap

Still, considering every thing Ive been thur with this build, there is really nothing happening here that im going to loose sleep over...pretty much basic par for the course Ive been on...Im just glad 1275s are plentiful and cheap here in the states

Prop
Prop


Oh dear Prop. You are cursed. Were you a very bad person in a former life?
GN Rowles

here are some various thoughts and notes Im thinking about that I said id post from my 1st post.

BTW...Im thinking the water in rad and massive oil pressure are unrelated...just a coincedince

Massive oil pressure simple as that!!!.....engine started and I set the engine to 2500rpm and the oil pressure was hitting 80psi, and lots of oil shooting out the rear scroll seal area the equvilat both in volume and force of a MANLY Pee Stream .... THEN when the thermostat opened I got a fountian of oil 3 feet high out of the vent in the oil cap, and both carbs was shooting oil out the carb mouths (HS2), and the rad was making lots of heavey whipped cream at the rad mouth, and later inspection showed minor oil in the rad but no apperance of water in the sump...this was in a time frame of 3 minutes

heres what I got,

The NEW Aftermarket oil by pass valve (cap, spring, and plunger) is a 1/2 inch longer then the orginal assembly...(part of the problem I guess)...

I revamped the evac system .... A year before the engine blew up, I converted the timing chain cover to an earlier modle without the canister/hose connection and tapped the engine block at the fuel pump metal blub area on the side of the block and vented it to the HS2 carbs...(No issues)

So the new system I have a vent hose on the mechanical fuel pump metal blub area going to a pcv valve thats 45-ed to the exhaust pipe after all the curves, so should be no backpressure...unless the worn out muffler is creating it,..... then tapped the valve cover installed a Pcv valve and vented to the carbs (HS2)

So tonight I re-hooked up the EVAC system back to the orginal way I had it a year before the engine blow up with the vent hose from the fuel pump blub vented back to the carbs,,,I did have excesive oil in the hose at the Pcv valve thats attached to the exhaust pipe...So I figure I got good suction , or alot of pressure... and at the end of the 3 minutes it was smoking ALOT out the exhaust pipe ither do to the oil shooting out the mouth of the HS2 carbs or oil from the lower end vent hose...or both...If I overcome this and use the new evac system, Ill definatly need to do a catch tank

the only thing I can figure the oil pressure was so high it blew the head gasket, and when the stat opened it put extra force pressure into the system at the blown head gasket to creat the mess Im discribing (the head gasket is the payen composite)

The Only other thing I can think of as being an possiable cause is the -15 degree temps for 10 days straight from 8 weeks ago may have cracked the block or head...I was only running 25/75 anti to water with rad. flush simply because I was going to flush the anti/water after start up in the fall seaon before this project kept going and going well into winter, and now into spring. and heck summer is only 12 more weeks away...LOL


Like I said I got the orginal oil by pass valve assembly re-installed (the shorter one) and have the evac set-up back to orginal, when it worked before without issue.PLUS I figure Ill pull the thermostat to take out any additional pressure situations and give that a try....Bad news is it will be late next week before I can try and do another restart. with these corrections

Prop

Gn...

According to my astroligist/palm reader...I was a Gangous kahn warrior, Nero's personal fire match maker, and an exaicution cross builder in jerusleum in the year 33 AD...Nah, Im not cursed...LOL
Prop

One step at a time as they say, back to post number 1 and card number 1 not far eh

""1st card...New oil pressure valve was stuck wide open and is 1/2 inch longer then orginal.""

In a normal engine the valve OPENS to REDUCE pressure, thus why would yours be stuck open yet give GOOD oil pressure? Perhaps you have that wrong? or maybe I do?

The reason I say good oil pressure, is because 80 psi is not unusual in fact I ran an engine for years that had high (80psi)oil pressure and thought it marvelous

You need to seriously understand why oil is being blown out of the engine by high crankcase pressure!
Robert (Bob) Midget Turbo

great point Brad....

over filling oil may be in the list of possiblities.... cant remember how much I put in the sump, But Im not sure if I took that into account when I also filled the oil filter and added a bottle (2 pints) of lucas break in additive....with everthing Ilost yesterday, Im still showing full on the dip stick

I did get smoking after about 1-2 minutes from the exhaust, and the oil shooting from the carbs I belive to be the result of the vent hose connected to the valve cover

Im certian the engine smoke came from the evac system...and not failing rings

So will find out hopely this next week...But like I said, Ive still got hope of a last minute repreve from the gods of vengance

Prop

Prop

On the oil pressure by pass valve I say stuck because On the new oil pressure valve the 9/16th inch ball bearing was stuck inside the block and took some convining to release...and the entire assembly compared to the old orginal assembly is a 1/2 inch longer...

I had hoped for 60 to 70, but there is a genral consensious that 80 to a 100 is okay for a new engine.

the reason for the new oil pressure assembly???...I broke the cap at the base where the cap meets the threads on the old one when removing with an electric impact wrench

Prop

What is the likely hood that the missing restrictor plug in the crankshaft could be the problem....there never was a firm consencios if it was really needed or not...kind of a start it and see what happens approach...it is a EN40b crank
Prop

sorry another note on the oil pressure valve...I have the valve fully open, if you screw the knob in, you get more oil pressure.

prop
Prop

Prop,
Put your old evac system on (or better still the original one !) the new one seems doubtful (exhaust pressure - if not used correctly is dangerous).

If you have grossly overfilled it - oil will pump out everwhere - happened to a fellow MG owner last year on a B - had me inspect the problem and he had lost 2 pints on the floor/engine coated, with a full dipstick !

Even with a good engine rebuild you must expect large quants of smoke - all that rebuild lube burning off.
In your case with everthing now coated with excess oil it will take a while as even the exhaust will be internally coated etc.

Best of luck - if 1275 are plentiful why not get one, stick it in and enjoy the summer and sort this one at your leasure.

R.
richard boobier

Hey richard.

moving the evac back to orginal before the blow up is my wild ace of spade card

As to another engine....MMMmmm, Yeah thats not really writtrn in the stars. Failure and abandonment is just not going to work at this point in the game, maybe a year ago, but just no longer a viable option....Dam the terpedos ... Full bore ahead

Prop... Thrish pulling it with a rope, is the least I can except
Prop

When you say 3 ft out of the oil cap - do you mean the cap on the rocker cover ?
Dean Smith ('73 RWA)

Prop - WHY are you torturing yourself in this manner? Even IF you were all of those things in previous lives, then, the karma kickback wouldn't be this bad!!!!
rachmacb

How many piston rings and head gaskets were left over once you bolted the engine together?

FRM
Fletcher R Millmore

Throw that engine in the bin and go buy one that works from someone who knows what they are doing.

Just how much oil do you have in the sump?
maybe you should drain it and refill with the correct amount.
Tarquin

just a thought, you didn't powder coat the block deck did you?
Tarquin

No Tarq just the copper head gasket.
Brad (Sprite IV 1380)

Powder coated head gaskets do look nice though.
Guy Weller

So do pistons, no need for rings then :-)
Brad (Sprite IV 1380)

http://www.skiptune.com/engines.html

i'm sure they will ship if you ask politly
Onno Könemann

LOL..

The dip stick is showing 1/2 quart low, The oil that shot out the oil cap on the valve cover was more of a fine mist....ill see if I can post some pics in the next several days.

Luckly I only had 3 parts left over after. the build...all various washers

See even you guys are starting to SEE of the value of powder coat...Its funny you mentioned powder coat the pistons, because I was really thinking about doing a ceramic coating on the piston tops during the planning stage....But on a more practical approach I may strip the carbs down and powder coat them, after all I still got to do the roll bar, have a couple engine parts redone that got scared up, and the suspension pieces.

seriouly guys I certianly appericate the input, But I wont know anything till wed. And frankly I really think its a matter of hunting down and killing another gremlin ...I really dont think I have much to worry about. the main thing is the engine starts, so its all down hill from there...Im pretty sure NOT even I can be that un-lucky to have a cracked block

So have fun, Ill keep you guys posted as to the problem

Prop
Prop

So basically you are saying we need to start a new book on when it will start and when hell freezes over is too early?!

Heck I would reckon that Bob would consider donations to his excess luggage allowance to carry a new engine ...

Is it actually making any attempt to work and it's going to be next winter again soon .........
rachmacb

Prop
Maybee the best way to go would be to diconnect your evac stuff and just vent to atmosphere for now to eliminate that as a cause of your problems----At least that will stop the crankcase from being pressurized.
With that done-hopefully there will be no oil squirting out
Next problem--
Them there are only three places that oil can get into the cooling system--
1-Cracked head - would be fairly unusual to crack from the oil hole I would think
2-Cracked block - possible but if it was from freezing I would think it would crack a bore or something before it cracked from a oil gallery but you never know I guess-
3-Headgasket - there is a chance here that it may have accidentaly got itself on the engine backtofront with the reinforced oil hole at the wrong end maybee ?????

Havn't had a whole lot to do with A series engines but if it were a B series that's what i'd be doing. Opening all the vents to at. and checking the gasket.
Cheers Willy Good luck mate.
WilliamRevit

This thread was discussed on 20/03/2010

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