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41 minutes ago, ntc said:

It is , just too help how old is the battery? It may crank but reduce power when needed ie cold 

And so will  faulty ballast resistor wiring in the ignition system. If you have a ballast resistor make sure it's OK and you're getting 12V to the coil on starting.

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On 10/12/2021 at 11:12 PM, Mike C said:

And so will  faulty ballast resistor wiring in the ignition system. If you have a ballast resistor make sure it's OK and you're getting 12V to the coil on starting.

A faulty ballast resistor shouldn't affect starting.  It is (or shoud be) bipassed/shorted out ofcircuit when cranking so that the coil gets a full 12v when starting.  A faulty ballast resistor tends to present as a car that starts but dies when you release the key.  On the 6's the ballast rsistor is actually within the wire rather than a stand alone resistor as found on some cars like the Spits and Stags unless it's been modified.

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20 minutes ago, Andy Moltu said:

A faulty ballast resistor shouldn't affect starting.  It is (or shoud be) bipassed/shorted out ofcircuit when cranking so that the coil gets a full 12v when starting.  A faulty ballast resistor tends to present as a car that starts but dies when you release the key.  On the 6's the ballast rsistor is actually within the wire rather than a stand alone resistor as found on some cars like the Spits and Stags unless it's been modified.

I mean , make sure that the coil is getting  the full 12V when cranking if the car is fitted with a ballast resistor.

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By the sound of it, my car is behaving like many others and that have to crack but over a number of time is normal.

It turns over really well, not lazy at all so I am pretty sure the battery is fine.

I am attending my first TR meet this evening so can chew the fat with local members and am sure there will be someone who can come take a looksee.

 

 

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On 10/12/2021 at 7:01 PM, Macleesh said:

Mine needs quite a lot of cranking if left for a while (weeks) That's even after leaving the pump to run for a generous period. However use it daily an it's pretty much "on the button"

I have the same experience,  starts on the button when used regularly but a bit of a bugger to start if left for several weeks. Just drive it often and enjoy it ! 

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Probably the best thing I’ve done on my car regarding starting and running was to change/renew the injector O Rings.

This is a really simple job and for about £10 you have enough  O rings to change them every year for about 10 years or more if you so desire.

This absolutely transformed my car. The old o rings were completely square in profile and providing virtually no seal, hence pressure would not be maintained in the lines when the engine wasn’t running. This led to difficulty starting if it had been standing and then, as is often described by others, it started on 3 or 4 cylinders then gradually 5 and 6 kick into life (normally, although sometimes it would just run on 5 cylinders).

Changing the o rings means that it starts pretty much first time now even when cold and been standing for weeks. Runs soooooo much better too, I say it’s like a “normal”car now!

It really is an easy job so would seriously recommend doing this. No need to pay silly money for someone to refurbish your injectors either……at least as a starting point.

Good luck! I hope you enjoyed your first Group meeting.

Cheers, Rob.

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14 hours ago, Rob Y said:

Probably the best thing I’ve done on my car regarding starting and running was to change/renew the injector O Rings.

This is a really simple job and for about £10 you have enough  O rings to change them every year for about 10 years or more if you so desire.

This absolutely transformed my car. The old o rings were completely square in profile and providing virtually no seal, hence pressure would not be maintained in the lines when the engine wasn’t running. This led to difficulty starting if it had been standing and then, as is often described by others, it started on 3 or 4 cylinders then gradually 5 and 6 kick into life (normally, although sometimes it would just run on 5 cylinders).

Changing the o rings means that it starts pretty much first time now even when cold and been standing for weeks. Runs soooooo much better too, I say it’s like a “normal”car now!

It really is an easy job so would seriously recommend doing this. No need to pay silly money for someone to refurbish your injectors either……at least as a starting point.

Good luck! I hope you enjoyed your first Group meeting.

Cheers, Rob.

Rob - thanks for this.

I assume I can get the O rings from the likes of Moss or is there a better supplier.

It also sounds like a job I could tackle myself which would be a bonus.

First meet with the North London group was good thanks, welcoming and friendly and some sound advice. Of and a little “banter” around my choice of car which made it ran enjoyable evening.

 

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Hi Scaf,

You can buy them from all sorts of online stores that sell o rings - you don’t need to buy them from TR specialists at all.

I bought mine from a company called Polymax. You need 2 sizes and best to get them in Viton.

Sizes are 4.47mm ID x 1.78 CS for the small ones and 17.12mm ID x 2.62mm CS. These probably correspond to imperial sizes, but this is what it says on the packet. You’ll probably find there’s a minimum order charge, hence why you end up with so many!

Good luck when you do it. One good suggestion that was made to me it to remove the very small cut lip from the end of the injector in a plastic bag so that if it pings off you know where to find it!

Cheers, Rob.

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Hello All

Can anyone explain how to identify the 2 types of injectors (serviceable/non serviceable). I have a 1974 CR car & after reading this post I purchased the 2 types of O rings but can't see where the smaller ones are fitted. The injectors have the small clip which I removed but couldn't see any small O rings or where they would go. The common part number on the injectors is 73125 with varying pre fixes & suffixes on each of the injectors. For example No1 is 19 72 73125A while No5 is 29 73 73125D.

Thanks

Alan 

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Hello again,

Slightly red faced ! Just found a diagram that shows the poppet valve (tip) comes out from where the fuel enters. As I hadn't removed the fuel line this wasn't obvious - did wonder what the hell the clip was actually doing  - doh.

On a positive note I changed the large O rings that seal the injectors to the body & it fired up first time after standing for 3 weeks. Something its never done. 

Alan

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16 hours ago, Mike C said:

"it fired up first time after standing for 3 weeks. Something its never done. " That's the advantage of  freshly bled injector lines.

And having an actual seal that maintains the pressure in the line while it is standing. That’s why it works the next time and the next etc. No need to depressurise each line.
I didn’t pay much attention to bleeding my lines after changing the o rings and never had a problem. At the pressure these run at can they really get an air lock?

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4 hours ago, Rob Y said:

And having an actual seal that maintains the pressure in the line while it is standing. That’s why it works the next time and the next etc. No need to depressurise each line.
I didn’t pay much attention to bleeding my lines after changing the o rings and never had a problem. At the pressure these run at can they really get an air lock?

There's usually a huge difference in startability between a PI car that's been left for 2 days and one that's been left for 2 months. I put that down to the PI system losing its prime.

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So today the car started well after being left for a week, but I did follow the various tips on left the pump build pressure and how to use the choke to best effect.

Harry gave the system the once over and pressure tested my Lucas pump which only 5psi off of ideal so not really likely to be a problem.

However, replacing the pump and the various rubber fuel pipes seems like a good investment, so that might be a winter project.

Thanks everyone for their input

 

 

 

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Good Result Sam. 

After reading this post I changed both types of seals this week. I finished changing the small seals today & took the car for a 10 mile run. Definite improvement in responsiveness & running. Job worth doing for the small cost of seals, however the job was a bit fiddly & not without risk. If you're  not confident the £70 or for reconditioned ones is a good investment.  I found if the original filters are fitted the poppets are quite a tight fit. No way would they just blow out-I had to gently drift them out & back in. Very nervous point given 50 year old plastics!.  I fashioned a punch with a 1.5 x 5 mm recessed hole in the centre for the tip to locate into. 2 injectors had  seals fitted in the past & had no filter fitted. These came out easier. Some of the injector bores have a slight step in reduction about half way down. I think this is for the filter to seat against. Its easy for the round section seals to catch on this & nick the seal when installing the poppet valve. I had to redo one. WD40 makes it slightly easier. I had read somewhere the original seals were round in section, however I'm doubting this as the 4 original injector seals were square section and this would have made assembly easier too reducing the risk of nicking the seal.

Incidentally where filters were fitted the was a small amount of debris in there. I guessing these are no longer available but they were fitted for a purpose so my advice would be to refit them if you have them.

Big thanks to all on this post for bringing it to my attention.

Alan  

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As the person that reconditions the £70.00 exchange injectors I can assure you that there is more to it than simply fitting new seals. When I carry out the service I reseat the pntle to it's seat this is to give the best possible spray pattern. Each injector is tested for both opening pressure and operation.  I hope this information helps members. 

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Hi Neil,

there is no need to convince me!
You did an excellent job on my PI equipment, is was one of the very few “fit and forget” items during my restoration.

Cheers,
Waldi

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2 hours ago, Waldi said:

Hi Neil,

there is no need to convince me!
You did an excellent job on my PI equipment, is was one of the very few “fit and forget” items during my restoration.

Cheers,
Waldi

 

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