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64EK26

Bedford 28HP engine problem

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Finally got my rebuilt engine running...

But I do have a few issues

1)      There is leak on the carb where the choke assembly attaches to the main body.

On the carb front does anyone have a copy of  the Solex instruction book called "Self-starting Solex Carburettor 35 & 40 RZFAIP downdraught governor type with accelerating device instruction booklet” , the IWM have a copy but you can’t down load it

Does anyone know what the suffixes on the 35RZFAIPO carbs mean ? and which ones are suitbale for an MW ?

2)      The oil pressure is very low and the oil pressure warning light only goes off when the engine is revved slightly, oil does flow up to the rockerbox. I am currently running the engine with no advance retard mechanism and no oil/air bath filter and using 20w-30 running in oil – Obviously there could be many reasons for this.

I am going to look at them in the following order

a)      Add felt seal on dipstick

b)      Re-clean the oil strainer, also check that the seal on the cover plate is good

c)      Double check oil level in sump

d)     Confirm that the distributor dog drive is fully engaged with the pump and is not just rubbing against it, possible cause of this is if the oil pump was pushed down a bit when the distributor was fitted. (If it was not engaged at all, there would be no oil pressure)

e)      Test oil pressure gauge

f)       Change oil to 30w

Any other suggestions before take the oil pump out ? as  this would seem the prime suspect

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If the locking screw for the oil pump (below the one for the distibutor) is fitted correctly then the pump should be fully engaged with the distributor gear. One thing to check is the cover plate over the oil strainer, just in front of the distributor, this needs to be air tight else the pump will be trying to draw air in. Assume you have the correct size bearing shells for the size of crank journals? Also, could be an issue with the oil pressure relief valve in the pump.

Did you remember to fit the oil feed pipe to the rockers?

Richard

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2 minutes ago, Richard Farrant said:

If the locking screw for the oil pump (below the one for the distibutor) is fitted correctly then the pump should be fully engaged with the distributor gear. One thing to check is the cover plate over the oil strainer, just in front of the distributor, this needs to be air tight else the pump will be trying to draw air in. Assume you have the correct size bearing shells for the size of crank journals? Also, could be an issue with the oil pressure relief valve in the pump.

Did you remember to fit the oil feed pipe to the rockers? 

Richard

Thanks Richard,

1) Cover plate is item 2b on my list

2) The crankshaft was polished and I re-used the shells, as these had no wear on them, the main problem was with the pistons, verly slight lip, and minor corrosion, so +0.020 re-bore and pistons. The engine is post war and was overhauled by bedford. I can only assume that the correct shells were fitted at that time.

3) I have ordered a new spring for the pump and will re-check the clearances, there was some wear on the pump, but though that it was OK (maybe I was wrong)

4) Oil feed pipes are connected to the rockers (bit of a fiddly route through the head)

Cheers

Richard

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Solex letter codes

Définition des lettres servant à désigner le type de carburateur et gicleur Solex
 

A Starter 2 positions Ga Gicleur d'air
AT Thermostarter progressif Gs Gicleur d'essence (starter)
B Bistarter u calibreur d'air
C Corps-cuve a Ajutage d'automacité
D Carburateur cuve droite Gp Gicleur de pompe
G Carburateur cuve gauche Gu Gicleur d'utilisation
H Carburateur horizontal I Injecteur de pompe
I Carburateur inversé H Injecteur de pompe haut
L Corps renforcé B Injecteur de pompe bas
P Pompe de reprise s Tube d'émulsion
R Régulateur F Flotteur
RR Régulateur à vitesse variable    
S starter    
T Thermostarter    
V Carburateur vertical    
X Carburateur à gaz    
K Buse/choke tube    
G Gicleur principal/main jet    
g Ralenti/auxiliary

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32 minutes ago, 64EK26 said:

Thanks Richard,

1) Cover plate is item 2b on my list

2) The crankshaft was polished and I re-used the shells, as these had no wear on them, the main problem was with the pistons, verly slight lip, and minor corrosion, so +0.020 re-bore and pistons. The engine is post war and was overhauled by bedford. I can only assume that the correct shells were fitted at that time.

3) I have ordered a new spring for the pump and will re-check the clearances, there was some wear on the pump, but though that it was OK (maybe I was wrong)

4) Oil feed pipes are connected to the rockers (bit of a fiddly route through the head)

Cheers

Richard

Sorry, saw you mentioned cover plate after I posted.

When re-using bearing shells it is a good idea to check the bearing clearance as it is not really possible to ascertain how much a shell bearing has worn without using something like Plastigage, which gives a good idea of any problems. Measuring the journals with a micrometer to check for ovality is wise to.

I am currently rebuilding a 28hp engine from a MW, this engine was rebuilt by Vauxhall Motors in 1954 and was well overdue for a rebuild.

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5 minutes ago, Richard Farrant said:

When re-using bearing shells it is a good idea to check the bearing clearance as it is not really possible to ascertain how much a shell bearing has worn without using something like Plastigage, which gives a good idea of any problems. Measuring the journals with a micrometer to check for ovality is wise to.

All the journals on the crankshaft were checked, all within the required tolerance and no ovality. With hindsight I should have carefully checked the clearance using plastigage or similar, they felt and looked fine.

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Thanks guys

All sorted - it was a bad seal on the oil strainer cap

Good oil pressure

IMG_5185.thumb.JPG.2ad52d8bc7498d8eb0a7e573f48fb9f5.JPG

The pressure gauge reads a bit high so prbably about 25-30 psi on idle and increases a bit when revved

Also the the carb has settled down and no leaks from the cold start(choke)

Runs quite sweetly

Onwards and upwards

Cheers

Richard

 

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1 hour ago, 64EK26 said:

Thanks guys

All sorted - it was a bad seal on the oil strainer cap

Good oil pressure

IMG_5185.thumb.JPG.2ad52d8bc7498d8eb0a7e573f48fb9f5.JPG

The pressure gauge reads a bit high so prbably about 25-30 psi on idle and increases a bit when revved

Also the the carb has settled down and no leaks from the cold start(choke)

Runs quite sweetly

Onwards and upwards

Cheers

Richard

 

Good one!

 

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