Essex V6 BV advice needed
Discussion
A good friend has sold me an essex 3.0 V6 BV engine needing a rebuild due to being a bit smokey on tickover.
I have pulled the heads of the engine and cant see anything wrong with the bottom end no lip on the bores no scoring of the bores, it has Hepolite pistons a Piper HR 270 cam the head has standard exhaust valve but the inlet is a massive 46mm its fully ported and polished as well.
Could the smoking have been the valve guides? I did remove an exhaust valve and it was pretty loose in the guide.
I didnt get the inlet manifold with this engine I do have a spare though but its just standard is it a DIY job to match the porting in the head to the manifold or is this net relly needed?
Will the 38 dgas Carb be ok with this engine or will I need to upgrade it.
last question what sort of power can I reasonably expect from an engine of this spec
cheers chris
I have pulled the heads of the engine and cant see anything wrong with the bottom end no lip on the bores no scoring of the bores, it has Hepolite pistons a Piper HR 270 cam the head has standard exhaust valve but the inlet is a massive 46mm its fully ported and polished as well.
Could the smoking have been the valve guides? I did remove an exhaust valve and it was pretty loose in the guide.
I didnt get the inlet manifold with this engine I do have a spare though but its just standard is it a DIY job to match the porting in the head to the manifold or is this net relly needed?
Will the 38 dgas Carb be ok with this engine or will I need to upgrade it.
last question what sort of power can I reasonably expect from an engine of this spec
cheers chris
Chris, that head spec sound like it could be an Essex Engines head - http://www.essexengines.com/cylinder%20heads.htm
GadgeS3C said:
Chris, that head spec sound like it could be an Essex Engines head - http://www.essexengines.com/cylinder%20heads.htm
Cheers I will give them a call tomorrow and see if they do an inlet to match the heads.Chris
valve stem having play is not good and have an effect on oil-consumption / blue smoke.
ford used such black rubber hat-shaped stemseals in the 70ies...often they became loose and moved up and down togehter with the valves (or did they do this in first place already?)
anyway: modern ones, which remain fitted to the head and have a spring loaded lip around the valve stem will do a much better job, even when the valve stem would have play inside the guides.
it could be also a cracked oil-scrapper ring on a piston.
does the car have a single or double exhaust? if double which cylinder bank was smoking?
ford used such black rubber hat-shaped stemseals in the 70ies...often they became loose and moved up and down togehter with the valves (or did they do this in first place already?)
anyway: modern ones, which remain fitted to the head and have a spring loaded lip around the valve stem will do a much better job, even when the valve stem would have play inside the guides.
it could be also a cracked oil-scrapper ring on a piston.
does the car have a single or double exhaust? if double which cylinder bank was smoking?
Many thanks for the info. The heads are single exhaust. I have no idea which cylinder was smoking as they all looked pretty similar and I have never heard or seen the engine run. I did do the pop test where you put a finger over the guide and pull the valve out quickly the inlet gave a nice pop as it exited the guide but the exhaust didn't it was also fitted with the umbrella type seals that can move up and down the valve so as you say any play will just let oil gush down the valve.I have now sent the heads to a local engine builder to be crack checked New valve guides and seals and skimmed. The bottom end looks in great condition no marks on the bores and no noticeable wear lip at the top. Fingers crossed when I get the heads back it should be ok.
Chris
Chris
chris52 said:
Many thanks for the info. The heads are single exhaust. I have no idea which cylinder was smoking as they all looked pretty similar and I have never heard or seen the engine run. I did do the pop test where you put a finger over the guide and pull the valve out quickly the inlet gave a nice pop as it exited the guide but the exhaust didn't it was also fitted with the umbrella type seals that can move up and down the valve so as you say any play will just let oil gush down the valve.I have now sent the heads to a local engine builder to be crack checked New valve guides and seals and skimmed. The bottom end looks in great condition no marks on the bores and no noticeable wear lip at the top. Fingers crossed when I get the heads back it should be ok.
Chris
46 mm inlet is stage three I think ? Have yourselve a read of the Burton' tuning guides on that...Chris
Coupled to a single carb, well ported inlet manifold with a properly set up and jetted carb you should see +180 bph at the fly
chris52 said:
Many thanks for the info. The heads are single exhaust. I have no idea which cylinder was smoking as they all looked pretty similar and I have never heard or seen the engine run. I did do the pop test where you put a finger over the guide and pull the valve out quickly the inlet gave a nice pop as it exited the guide but the exhaust didn't it was also fitted with the umbrella type seals that can move up and down the valve so as you say any play will just let oil gush down the valve.I have now sent the heads to a local engine builder to be crack checked New valve guides and seals and skimmed. The bottom end looks in great condition no marks on the bores and no noticeable wear lip at the top. Fingers crossed when I get the heads back it should be ok.
Chris
Hold off skimming the heads?????Chris
Are they warped? Do you know the engines compression ratio?
Are you prepared to machine and port match the inlet to match a pair of skimmed heads?
If this is an already tuned engine with worked heads then skimming them further may do you more harm than good!! You need a dry build and a combustion chamber volume calculation before you skim anything.
N.
Bronze guides have self lubricating properties and allow you to run a closer fit tolerance with the valve, This gives better oil control, more valve stem support and generally a quitter more refined valve train.
With respect to inlet matching..I don't think the OP grasped the issues around head skimming on a V8 / V6 engines (In general). On any V engine with a wedge type inlet manifold if you skim the head surface then you correspondingly lower the head and hence inlet ports which necessitates ensuring you machine a corresponding amount of the inlet to ensure a proper joint between. This obviously depends upon the type of engine but the principles usually hold up, it can be a more pronounced issue on certain engines than others dependant on the angle of the port faces.
If this engine is unknown to you then you really need to be measuring it in all planes to ascertain how it has been built and which bits have previously been shaved.
N.
With respect to inlet matching..I don't think the OP grasped the issues around head skimming on a V8 / V6 engines (In general). On any V engine with a wedge type inlet manifold if you skim the head surface then you correspondingly lower the head and hence inlet ports which necessitates ensuring you machine a corresponding amount of the inlet to ensure a proper joint between. This obviously depends upon the type of engine but the principles usually hold up, it can be a more pronounced issue on certain engines than others dependant on the angle of the port faces.
If this engine is unknown to you then you really need to be measuring it in all planes to ascertain how it has been built and which bits have previously been shaved.
N.
Dollyman1850 said:
Bronze guides have self lubricating properties and allow you to run a closer fit tolerance with the valve, This gives better oil control, more valve stem support and generally a quitter more refined valve train.
With respect to inlet matching..I don't think the OP grasped the issues around head skimming on a V8 / V6 engines (In general). On any V engine with a wedge type inlet manifold if you skim the head surface then you correspondingly lower the head and hence inlet ports which necessitates ensuring you machine a corresponding amount of the inlet to ensure a proper joint between. This obviously depends upon the type of engine but the principles usually hold up, it can be a more pronounced issue on certain engines than others dependant on the angle of the port faces.
If this engine is unknown to you then you really need to be measuring it in all planes to ascertain how it has been built and which bits have previously been shaved.
N.
I did understand your meaning but I appreciate your explanation anyway. What I was trying to say was that I dont have the original inlet so everything will need to be done in order to match the ports. But as you say this cannot be done until the engine has its heads back and in place. I do not know the engine but the chap it came from did and it was described as a very quick engine with the only fault being a bit of smoking when it was idling. The engine came out of a 3000s and was the original block that was supllied with the car. It has obviousley had sone work done on it. I thought that the pistons were Hepolite ones but it turns out that they are just standard on a standard bore. So the bottom end has done 94k miles. This build is really just to get the car on the road and long term I intend to build a much better bottom end, I have another good block crank etc and a set of .90 hepolite pistons but I may need to get new liners in the block to take this size piston. This build though will have to wait until I get this car and the Vixen completed.With respect to inlet matching..I don't think the OP grasped the issues around head skimming on a V8 / V6 engines (In general). On any V engine with a wedge type inlet manifold if you skim the head surface then you correspondingly lower the head and hence inlet ports which necessitates ensuring you machine a corresponding amount of the inlet to ensure a proper joint between. This obviously depends upon the type of engine but the principles usually hold up, it can be a more pronounced issue on certain engines than others dependant on the angle of the port faces.
If this engine is unknown to you then you really need to be measuring it in all planes to ascertain how it has been built and which bits have previously been shaved.
N.
thanks again guys for all the input help and advice it really is appreciated
chris
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