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MG Midget and Sprite Technical - thin /thick flange?
Since my engine keeps pissing out oil i will need to do some work on it But it is a thin flange block 1340 balanced and lightend with a 731 cam and a osselli head How mutch of an advantage is a thick flange block over my thin flange?? and is it posible to get a bare fwd a-series thick flange block and just use the bare block to rebuild my current engine? |
Onno Könemann |
Onno. Sorry to hear about your spin.... hope the damage is not too bad. As for the engine, forget going down the FWD block route unless you just want to throw money away.. Yes, it can be done but the cost is quite prohibitive. The thin wall block should not give any trouble with oil leaks if built properly. Where is the oil coming from? Have you checked worn or broken piston rings? or even broken pistons? The Thick flange block, like the thin flange version is not easy to come across but I'm sure that if you are at the mg spares Day at Stoneleigh in a couple of weeks, you should find one. I also think there are a couple on Ebay at the moment and with the strength of the Euro against the GB£, everything will be relatively cheap..... Good luck, Mark. |
Mark T. Boldry |
last time I cleared al the sump vents and hoped the best because one was realy badly blocked the rings are my first suspect but on that i will know more when i do a leak down or tear down the block. No smoke clouds and clean plugs so it is not burning it So my first idea is to mutch pressure in the sump (broken rings) but since it already is a 1340 (if my info is correct) I am a bit scared with the prospects of over sizing About the fwd block I thought it was the front and back plates and the crank whom are diffrent. And I already have those. I assume from you comment there is more to do? stoneleigh is not a bad idea i won't come my self but a friend of mine is (and he builds blocks for a living) maby he will beable to pick something up |
Onno Könemann |
Onno, I have a spare thick flange inline block that might do. I should be going to Stoneleigh so can bring it with me no problem. matt at v8midget dot com Matt |
Tarquin |
Onno, I hope the damage you mentioned in another thread is not too bad and can be repaired easily. Regarding the oil leak, I would find it interesting to know where the oil is coming from or being lost out of. My experience with a few worn and new A series is that I have only had an oil loss of that magnitude on 2 new A series in about the first 50 miles when the rings were bedding in, otherwise oil use about what would be expected for an old design engine and tuned, ie nowhere near what you mentioned. That was oil passed into a catch tank via the breather tubes, the rest of the engine being pretty oil tight even with the old rear scroll seal. The last engine was a 1380, stroked to 1420, and thin flange. IIRC the thick flange and later ribbed engines were better but for road use not essential. My last engine was the 1420 with Kent 286 and Dellorto 40 DHLA, the crankcase venting being via two 1 inch vents, one from the fuel pump port via an oil separator and another from the rocker chest, pretty standard for racers IIRC although this was primarily a road engine. This issue comes up constantly on the board and some say one must have negative pressure and others live with big vents like I did quite happily. It would be great to have the ability to do a detailed diagnosis of the cause on an engine by engine basis and add it to a FAQ but it's unlikely to happen I think. |
David Billington |
Onno I have a friend in the Netherlands who has converted FWD A-series to inline. Alternatively, he may have a Midget block or engine available. Give him a call... Ton Blankespoor 0629 448557 |
Dave O'Neill 2 |
thanks for all the info the midget will go to the shop for the other damage and we will make a plan for the engine The oil is lost around the back side of the engine though the whole engine "sweats" a bit If needed i wil check the dutch engine lead first otherwise i wil contact Matt |
Onno Könemann |
... crankcase breather? A |
Anthony Cutler |
those are clear and fine now one on the rocker and one on the timing cover venting to a catch tank I know some people think it shoud hav a vac supply but I know of at least 3 hot A-series engines with the same breather setup and no oil spil problems When I droped it of at the shop this morning one plug was black and oily so the engine will be pulled soon |
Onno Könemann |
This thread was discussed between 08/02/2009 and 09/02/2009
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