| Author |
Message |
John Rigby (65.112.227.94)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, April 21, 2004 - 2:05 pm: | |
On really checking into my injector type and sizing, here our several bits of info they don,t tell you.Probably becase most people dont know.
I did not know that most injectors have small replacable filters, that are there for protection in case you pick up bad fuel, that makes its way past the filters. These filters are located on the incoming side of the cross over, you pull the coss over tube off, then unscrew the nut it fastens to and use an ice pick and pluck the little filter out. I was advised to keep a complete set with me plus replacement overhead tubes( for my 671 = 6 filters plus 6 new tubes total cost $30.00)The filters are only on the in coming fuel side of the injector.
My injectors it appears are the very old HV 70/N70, The place were tubes attach are parrellel.
The new type are offset.
The bottom of the HVN70 looks like the new style N70, but per DETROIT they should not get retofitted as the spray is different/better, and will over heat the top of the piston.
I like knowing that the injector has its own filter and that it is added protection.
I wounder if injectors have been changed, the rack run and all it needed was a new filter??
John |
Geoff (Geoff) (66.238.120.17)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, April 22, 2004 - 9:31 am: | |
The only time those injector filters are changed is when the injectors are overhauled. They are there as a safety measure to make sure nothing gets into the injector mechanism, but under normal circumstances the fuel filters will pickup any dirt or foreign material in the fuel.
Your N70's have been converted from HV7 bodies. This means you have the newer style, high compression "N" pistons but you are still using the original 2-valve head.
--Geoff
'82 RTS CA |
John Rigby (65.112.227.94)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, April 22, 2004 - 12:30 pm: | |
Geoff
S and W did say not to change over to the new style as they do spray diffrently?? and could put to much heat on top of the piston. We put both the new style and old next to each other. yes the top as you said is diffrent, the bottom looks the same. But the spring in the new style is twice as big and heavy as the old style. Does this make the diffrence??
Also is it a waste of time to keep new injector filters and overhead tubes with me??
John |
Jose (63.190.105.171)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, April 22, 2004 - 4:31 pm: | |
Use caution if You use the "Injecter Secret Fix"
The injecter body must be absolutely clean when You pull that internal filter, be careful of tiny bits of dirt, watch your shirt sleeves, tools,etc.
The diameter of the spray tip holes are .005 or
.006, the clearance between the plunger and sidewall is nill.
I believe that filter is actually their to protect the injecter from any thing in the lines after they have been off and replaced.
In 1957 I took a cource in injecter-pump repair
the last thing the instructor said was " If you arent in a clean pressurised room leave the damm things alone "
Jose
A dumb, retired mechanic |
Geoff (Geoff) (66.238.120.59)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, April 22, 2004 - 10:08 pm: | |
John-- you are confusing me on what you have, but the answer is to only put back what you took out-- if you took out HV7's, you have to go back with HV7's, do not put N70's unless you have changed the pistons over to the higher compression "N" type of pistons.
To answer your question, it is never a bad idea to keep a couple of extra fuel lines with you in case one cracks and starts leaking. The fuel screens you don't need. And thanks for your imput, Jose-- your advice is right on (and you are not dumb!!).
--Geoff |
John Rigby (65.112.227.94)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, April 23, 2004 - 9:30 am: | |
Geoff
I have the very old style N70 for the 2 valve head/ high com pistons /advanced timing.
Thanks
John |
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