New fuel pump install

Well my new fuel pump arrived. I ordered the Bosch but got substituted with the Spectra. Not sure which one is better.
Also is there a per litre measurement one should look for.
I was also looking at the book, looks like at good opportunity to upsize the wiring from power , relay and ground to a # 12 AWG stranded.
Is there anything else I’m missing here. Looks like a simple enough job. The Bosch performed like a trooper. No issues with it , just thought it was time to replace before the warmer weather and driving season hits.

Bosch pump has a brass output end and into it is threaded a brass one way check valve which usually ships already attached. Don’t see anything in screen grab that looks remotely similar.

Personally, I would not touch a performing quiet Bosch pump ever. You know the saying so I won’t repeat it.

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I would not personally remove and replace a properly functioning Bosch fuel pump with a modern aftermarket one. But it is your car.
If you do remove and replace your Bosch pump, make sure you observe proper polarity with the new pump wiring for the aftermarket pump. The “+” and “-” connections on some of the aftermarket pumps I have seen in my parts cars were reversed on the pump and very small and difficult to see.


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If anything a $40 spare would do for emergencies, there’s no common reason the current pump should fail during normal use…

I’m thinking some reverse engineering here.
I’m going to keep the Bosch as my backup spare.
On 40C days it can sound buzzy. Less once I changed out fuel filters. But hey it’s almost 40 years old that was designed to pick up the slack of the fuel pressure and delivery demands of a fuel injected V-12 engine. We all know that a lot of electrical issues occur due to undersized wiring as suggested by Kirby, which I would think is a great upgrade. I don’t want to entertain the idea of a burnt out cylinder head due to voltage drop or old pump when better technology is on the market today.
Less resistive connection points and carbon commutators to deal with heat etc…
I’ll go in and keep you all posted.

If that is the original fuel pump at 40 years, nothing wrong with replacing it. But i would send that one back and find a Bosch. They are out there.

FWIW, i went with a Walbro. A bit longer and thinner, so it wasn’t plug and play.

I will more or less just repeat the previous replies. I tried a generic substitute but found it noisy and lacking non return valve.
Did not take long before it was replaced with genuine Bosch.

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I tried three, one bad, one acceptable, one great, and total cost was less than a good one - it’s a good spare. I‘ll say it now… if it ain’t broke, don’t fix it.

I tried one, after a couple of months it was irritatingly noisy…
Got a Bosch Turbine pump, works very well and it’s totally silent.

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Gary says it makes bad sounds when hot. It’s 40 years old. I agree with Gary, change it. Sure he could get more years out of it, but why be stranded on the roadside one day? Nothing lasts forever. It’s such an easy replacement on these cars.

Just make sure to go Bosch again.

OK all, you’ve convinced me , I’ll source a Bosch, it’s not a panic but goes on my summer ta do list. Did you guys increase the wire sizing to # 12 AWG stranded. I thought if I’m going in lets get er done properly as The Book would suggest.

I did not, works well as is.
Nevertheless, I never measured real voltage at the pump feed cables.
On the XJ that has the battery at the front it’s a big job to bring a heavier cable all the way back, for you XJS people it’s a piece of cake…!
Easiest done with the addition of a relay.

I dunno are we just becoming parts whores. I received my Bosch made in Czechoslovakia but my original one sure seems like a lot nicer product.

Heavy paint?! Lol.

Not sure how weight matters for fuel pumps. They’re both probably good, but I’d go with the Bosch. Never had issues.

I threw the weight thing in there for a few laughs. Good pick up Greg.
Old school more for the money. LOL!

Apologies, forgot to ask , how is your car running these days? What are your projects for this up coming driving season? Your’e always delving into something?

I’ve actually got little to do, which is nice for a change. I am going to attempt to rebuild my original power steering unit soon. I’m currently running a rebuilt unit, but it has a tiny leak. So thought I’d try myself. Will paint it too.

Did you get all your idling issues sorted out?
If I remember correctly tou were having some ip and down idling that needed smoothing out. Did you ever figure out the issues?

Bought cheapo to hot-swap until good ‘branded’ will arrive. It was sooooo cheap (eBay £20 Sterling) that actual spade connectors were assembled other way around. Complained and received another unit free of charge. Runs perfectly 3rd year. Spending 7 times more for without clear justification seems slightly off the roof. Just saying…

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Rolling the dice. I’ve gone cheap before, and most of the time the part does not last. Learned my lesson. I don’t like redoing the job.