MatraSport Forum

Each model => Murena => Topic started by: LarsB on August 31, 2010, 05:21:32 pm



Title: Where can I get main bearings?
Post by: LarsB on August 31, 2010, 05:21:32 pm
In the middle of my rebuild I discover that my crankshaft have been ground -0.10mm. I Need new bearings, but Simon doesnt have them  :(


Lars


Title: Re: Where can I get main bearings?
Post by: Matra_Hans on August 31, 2010, 09:02:25 pm
Thar is bad luck!

Hans


Title: Re: Where can I get main bearings?
Post by: michaltalbot on August 31, 2010, 09:08:18 pm
Mr.Milan Dobes has them, he is now renovating my engine so I will ask him for another set for You. Are You going to brush Your crankshaft to 0,25 or do You need 0,10?

Btw: I have to recomend to all - balance your crankshaft and flywheel when you have engine demounted. As I wrote to another topic, my engine was damaged because of using P505 oil pump which is 8mm higher, so in corners oil pressure went to 1 or 0, and it was looking like that only one small-end bearing will have to be changed. But we've also found that last main bearing is hardly damaged. So I bought another crankshaft and took it with my flywheel and with clutch pressure plate to one old specialist, who is doing balancing for cca 40 years. They say, that 5 grams on these components, could lower the engine effectivity for 5%. So when they started with my crankshaft, the whole machine vibrated hardly (and they told me, that there is 27 of hand-barrows of concrete under the machine) and the result was: 7,3 grams on pulley side, 4 grams on flywheel side and unbelievable 12 grams on flywheel! When they finished their work, the crankshaft + flywheel was just zoomed through the wind very quietly and on pulley side was 0,16 grams, on flywheel side 0,18 and flywheel itself had 0,16 grams, both parts mounted together and also together with clutch pressure plate had 0,16 grams at one side and 0,19 grams on another side. It was amazing difference and I hope that it will be noticeable on the engine also...


Title: Re: Where can I get main bearings?
Post by: krede on September 01, 2010, 01:51:26 pm
Hi Michal. I have had a Crank shaft reground to 0.2 oversize, but has so far not bought new bearings simply because of the cost (Simon)

What price does "Mr.Milan Dobes" charge for a set? (Main and  con rod) ?


Title: Re: Where can I get main bearings?
Post by: Anders Dinsen on September 01, 2010, 07:32:50 pm
Hi Michal. I have had a Crank shaft reground to 0.2 oversize, but has so far not bought new bearings simply because of the cost (Simon)

Oversize!! wow... that's going to revolutionize mechanical engineering  :P


Title: Re: Where can I get main bearings?
Post by: krede on September 01, 2010, 07:42:23 pm
Well.. the crank was worn and they had to grind it a bit. :-\.. it came from the engine I bought from Hans... The one I picked up at your place looks much better.


Title: Re: Where can I get main bearings?
Post by: Anders Dinsen on September 01, 2010, 07:50:19 pm
Well.. the crank was worn and they had to grind it a bit. :-\.. it came from the engine I bought from Hans... The one I picked up at your place looks much better.

You didn't get it... ;) shells are oversize. Crankshaft is ground down. Many an engineer has dreamt of the grinder that will add material... Sorry, I'm just trying to be funny... on your expense! I guess I failed miserably :( ;)


Title: Re: Where can I get main bearings?
Post by: krede on September 01, 2010, 07:54:19 pm
[bonk!!!]

Nope I didn't.... but of cause you are right... I meant 0.2 REPAIR size as is says in the Workshop manual.... my bad! ;)


Title: Re: Where can I get main bearings?
Post by: michaltalbot on September 01, 2010, 09:39:09 pm
Well, I asked Milan Dobes today and have this answer:

0,10 is no more available  :-[

Main bearings - there are two producers:
1) Italian - Nuova Boto - in 0,25mm size for 49,- Eur / set
2) French - original - in 0,20mm size for 99,- Eur / set

Small-end bearings:
Vanderwell from GB - not depence on size - 89,- Eur / set

 So bad news is that 0,10 is not available for more, so if You will brush the crankshaft, You have to decide first, if You are going to use Italian ones = brush it on 0,25mm, or original French ones, what means to brush it on 0,20mm value.


Title: Re: Where can I get main bearings?
Post by: krede on September 01, 2010, 09:51:49 pm
99 euros "set"... is that for all 10 shells ?



Title: Re: Where can I get main bearings?
Post by: michaltalbot on September 01, 2010, 10:27:54 pm
99 euros "set"... is that for all 10 shells ?

Of course, it is a set for all 5 main bearings = 10 shells. Do You know another "set"?  ;D


Title: Re: Where can I get main bearings?
Post by: krede on September 01, 2010, 10:34:50 pm
Michal!! you are my hero!!  :D

Well,,, I have seen two shells mentioned as a "set"......  and considering that Simon charges 261 Euros for a "set" of ten shells, I hope you will forgive me for asking! :)

How do one get in contact with Milan Dobes.? At that price I think I'll go ahead and order a set of small end and Main bearings straight away!


Title: Re: Where can I get main bearings?
Post by: krede on September 02, 2010, 10:46:40 am
Looks like Carjoy has Main Bearings in 0.1 oversize : 01047B

http://www.carjoy.nl/webshop/artikli.asp?id=1&model=5&pageNum_Recordset2=7


Title: Re: Where can I get main bearings?
Post by: Oskar on September 02, 2010, 11:05:48 am
is it the same crank as in peugeot 505 turbo?


Title: Re: Where can I get main bearings?
Post by: krede on September 02, 2010, 11:07:19 am
I have not been able to distinguish between the two, Other than that the 505 crank has 7 bolts for the flywheel (as do some Murena cranks I think)


Title: Re: Where can I get main bearings?
Post by: michaltalbot on September 02, 2010, 04:10:27 pm
Well,,, I have seen two shells mentioned as a "set"......  and considering that Simon charges 261 Euros for a "set" of ten shells...

 :o OMG! Not possible...

 Milan Dobes speaks English very well, so You can simply contact him on the email: pradomodel@volny.cz  ;)


Title: Re: Where can I get main bearings?
Post by: krede on September 02, 2010, 04:37:48 pm
Great! thanks a lot Michal... :)


Title: Re: Where can I get main bearings?
Post by: michaltalbot on September 02, 2010, 07:14:23 pm
You're welcome, but it belongs to Mr.Dobes, because he isn't thinking only about making money (as others do), but to help us ;)


Title: Re: Where can I get main bearings?
Post by: LarsB on September 02, 2010, 08:38:05 pm
wow, thanks for all the great information :)  So helpful to have a forum with so many knowledgeable people.

Now, Il have to confess that my original post was entierly wrong and it is the conrod bearings I need. As you have pointed out Simon and several others have the main bearings in 0.10 (thanks for reminding me of the cost  :-\)

I dont think I will balance the crankshaft, its overly expensive to do here in norway, and Il have to ship it to one of the larger cities.


Title: Re: Where can I get main bearings?
Post by: michaltalbot on September 03, 2010, 08:09:53 am
LarsB: how much does it cost in Norway? I've paid 80,-Eur.


Title: Re: Where can I get main bearings?
Post by: krede on September 03, 2010, 08:11:52 am
I paid some 200  just to have mine cut to 0.2 undersize!!


Title: Re: Where can I get main bearings?
Post by: LarsB on September 03, 2010, 08:44:05 am
I paid 400 to have the cylinders bored 

Balancing of cranckshaft, flywheel and clutch  is 300

Grinding and polishing of cranckshaft is about 500 ::)

These prices are from Cylmo.no  and motorverksted.no

If I where to do do more machining that Alfa V6 is starting to look like the cheap way out  ;D


Title: Re: Where can I get main bearings?
Post by: krede on September 03, 2010, 08:47:26 am
We should throw all of our stuff in the back of a lorry, and head down to visit Michal for a weekend... then we could "sample " the excellent beer they have ,while our engines got fixed cheaply !!! :D


Title: Re: Where can I get main bearings?
Post by: michaltalbot on September 03, 2010, 05:45:36 pm
Yes it seems that you have to make a trip to CZ ;) because renovation of my engine won't be more than 1000,-Eur complete...


Title: Re: Where can I get main bearings?
Post by: LarsB on October 16, 2010, 09:23:09 pm
I have been trying to order bearings from carjoy, but After the order confirmation I hear nothing from them. I have tried mailing them but get no reply. 

Do any of you know if something happend to the business?

-Lars-


Title: Re: Where can I get main bearings?
Post by: roy4matra on October 17, 2010, 04:26:04 pm
In the middle of my rebuild I discover that my crankshaft have been ground -0.10mm. I Need new bearings, but Simon doesnt have them  :(

Lars

I know most of you on this forum are used to measurements in metric, but we have to be very careful in quoting engine undersizes, since although this engine family (1639/1812/1984/2215cc) was made in Europe and generally metric measurements, it was designed in England to originally imperial measurements.  Why do you think the cylinder head block face to cover face is exactly 6 inches with a tolerance of 4 thou?  Why does it have many non ISOmetric 7 mm studs and bolts - they were originally 1/4 inch (which is larger than 6 mm).  Why is this important?  Because in the U.K. our undersizes were generally 10, 20, 30 and 40 thou. (thousandths of an inch)  So the first undersize of 10 thou is equivalent to 0.25 mm  whereas when you talk of 10 under meaning -0.10 mm that is only 4 thou.  It is unusual to regrind a crank journal or big-end pin to 4 thou undersize.  Most engines needing regrinding will have already gone past the 4 thou undersize.  So that size was really only for either badly machined original sizes or when cleaning up an otherwise good crank to put in new shells.

These days it is possible that certain bearing shells or crankshaft thrust washers meant for another engine may fit, but if they are made for an English engine the undersizes will be imperial not metric.  This is why there are 0.20 mm and 0.25 mm undersizes.  The latter are really 10 thou undersize.

So when you specify an undersize you need to make sure you specify whether you are talking about mains (10 half shells) or big-ends (8 half shells) and imperial or metric.  Finally you should NEVER have a crank reground without first having the bearing shells and providing the machine shop with them.  Why?  Because if they have the shells that will be used they will (or should if they are good) make sure the crank is ground to a good fit for the new shells.  If they only have the crank and grind it to a specified size, then find the shells are not quite right, they have to do the job over and may even have to take more off to go to the next size.  e.g suppose you had it ground to 0.25 mm (10 thou) under and then found the only shells available were -0.20 mm or -0.50 mm  You would then have to go to the -0.50 mm size as you were already past the -0.20 mm dimension.

I have and can get undersize shells and thrust washers for these engines now but one set of undersize shells I have for the big-ends is '10 under' - that is 10 thou under, therefore -0.25 mm.  And some of the packets for these parts are marked with other manufacturers names - like Vauxhall and Rover.

Hope this helps clarify things a little.

Roy


Title: Re: Where can I get main bearings?
Post by: LarsB on October 18, 2010, 05:45:09 pm
Good thing you got your eyes open.  I rechecked the measurement and it is 51.76mm wich is 0.20 undersize ;)

The crankshaft have been ground previously and does not need regrinding now

I also wish to thank you for the information regarding the common misstakes.

btw, you do not know of any oil-sump for sale? mine have had a conrod go thru it (probably the couse of the previous regrind)

regards
Lars


Title: Re: Where can I get main bearings?
Post by: Oetker on October 20, 2010, 08:10:02 pm
Quote Lars B
-----------------
I have been trying to order bearings from carjoy, but After the order confirmation I hear nothing from them. I have tried mailing them but get no reply. 
Do any of you know if something happend to the business?
======================================================================================================

Today I was at Carjoy.
Busy times over there.
Nothing wrong with the firm.
He told me he has little time to work on the administration.
If no reply, then mail again, or better grab the phone.