Cheap fuel pumps

D

DSpieg

True Classic
A caveat emptor to those who, like myself, have purchased any of the cheap blue unmarked Chinese electric fuel pumps which are available from a myriad of vendors.

I put one in my '87 X just a couple of months and maybe a thousand miles ago, and the other day I noticed it had gotten very noisy so I removed it over the weekend and threw it in the trash. Replaced it with a spare German-made OEM Bosch (much used but still working fine).

Sure, $20 for a new electric fuel pump is a heck of a deal, but sometimes you get what you pay for :)

I also put one of the Chinese Blue Bargains in my '87 Alfa Milano over the winter when I was restoring the car, and so far that pump is OK after about 4 months and 3K miles. But I'm keeping a spare in the trunk at all times.......
 
This has been a problem with the Abarth Swaps. The Abarth platform requires a fuel pressure of 58 PSI, the ECU does the calculation for injector duration based on this pressure. What I have found is that the fuel pump rotors which house the rollers will elongate in short order and fuel pressure will drop off and the result is a bucking engine. The issue at hand is that no vendor will guarantee that the pump they are selling is not of OEM quality even if it says Bosch on the box. Hence I always have a spare pump on hand. I have had pumps fail in as little as 2,000 miles. Currently I have an AEM pump sitting as a spare waiting for the pump in the car to fail. I am on the second fuel pump in 5,000 miles.

TonyK with Bob Martin in the Westland Texas
 
TonyK said:
This has been a problem with the Abarth Swaps. The Abarth platform requires a fuel pressure of 58 PSI, the ECU does the calculation for injector duration based on this pressure. What I have found is that the fuel pump rotors which house the rollers will elongate in short order and fuel pressure will drop off and the result is a bucking engine. The issue at hand is that no vendor will guarantee that the pump they are selling is not of OEM quality even if it says Bosch on the box. Hence I always have a spare pump on hand. I have had pumps fail in as little as 2,000 miles. Currently I have an AEM pump sitting as a spare waiting for the pump in the car to fail. I am on the second fuel pump in 5,000 miles.

TonyK with Bob Martin in the Westland Texas
Click to expand...
I know this is a little off topic but have you looked into the walbro pump range? They have offerings that last well over 150,000mi at 85-100psi in some applications, but many bosch ones do too so it makes me wonder why your pumps are dying so quickly. 2,000mi is mighty fast!

Many of these new pumps are designed to be fully submersed at all times though- as they sit in a jet pump fed bucket. Heat will kill them very, very quick.There are some that are designed to withstand not being submerged though, just depends on the model.
 
TonyK said:
This has been a problem with the Abarth Swaps. The Abarth platform requires a fuel pressure of 58 PSI, the ECU does the calculation for injector duration based on this pressure. What I have found is that the fuel pump rotors which house the rollers will elongate in short order and fuel pressure will drop off and the result is a bucking engine. The issue at hand is that no vendor will guarantee that the pump they are selling is not of OEM quality even if it says Bosch on the box. Hence I always have a spare pump on hand. I have had pumps fail in as little as 2,000 miles. Currently I have an AEM pump sitting as a spare waiting for the pump in the car to fail. I am on the second fuel pump in 5,000 miles.

TonyK with Bob Martin in the Westland Texas
Click to expand...
Tony, are you saying that Bosch pumps are failing in 2,000 miles, or the 'knock-off' ones?

Like @Jonohhh said, I've always found Bosch pumps to be extremely robust. I've used them for over 300,000 miles and still going strong with 90 PSI potential. However like every part manufacturer, Bosch has changed over the years. For one thing the company was bought by a larger conglomerate and the entire line of fuel pumps was significantly streamlined. In addition all models were redesigned with a different style internal pumping mechanism than previous models. Furthermore production takes place all over the world and not all sources offer the same quality; some are made to meet a price point for specific markets. So some new Bosch pumps may not be as robust as older models were, but I have not found any failures yet.


Jonohhh said:
Many of these new pumps are designed to be fully submersed at all times though- as they sit in a jet pump fed bucket. Heat will kill them very, very quick.There are some that are designed to withstand not being submerged though, just depends on the model.
Click to expand...
The style used on the X is designed to be cooled internally as the fuel passes through it. All Bosch pumps not intended for in-tank use are this way.


This topic kind of brings up some commonly heard misconceptions about these pumps. First, they do not have to be mounted below the level of the tank - they are very capable of drawing fuel up to the pump on a regular basis without damage. There are factory fuel system designs that have done this for decades. Second, running them dry for even a second will not damage the pump. They can run for reasonable durations (several minutes?) with no problems, however continuous dry running (i.e. very prolonged periods) can eventually overheat it. Third, the power supply (current to the pump) is critical for maximum performance. Often too thin of wire gauge is used, poor connections, etc, and the pump is misdiagnosed as bad. Another common issue is a heavily contaminated fuel tank clogs the fine wire mesh at the pump's inlet, starving the pump. That's not really a pump failure though. I prefer to install a pre-pump filter in every vehicle regardless.
 
Dr.Jeff said:
Tony, are you saying that Bosch pumps are failing in 2,000 miles, or the 'knock-off' ones?

Like @Jonohhh said, I've always found Bosch pumps to be extremely robust. I've used them for over 300,000 miles and still going strong with 90 PSI potential. However like every part manufacturer, Bosch has changed over the years. For one thing the company was bought by a larger conglomerate and the entire line of fuel pumps was significantly streamlined. In addition all models were redesigned with a different style internal pumping mechanism than previous models. Furthermore production takes place all over the world and not all sources offer the same quality; some are made to meet a price point for specific markets. So some new Bosch pumps may not be as robust as older models were, but I have not found any failures yet.



The style used on the X is designed to be cooled internally as the fuel passes through it. All Bosch pumps not intended for in-tank use are this way.


This topic kind of brings up some commonly heard misconceptions about these pumps. First, they do not have to be mounted below the level of the tank - they are very capable of drawing fuel up to the pump on a regular basis without damage. There are factory fuel system designs that have done this for decades. Second, running them dry for even a second will not damage the pump. They can run for reasonable durations (several minutes?) with no problems, however continuous dry running (i.e. very prolonged periods) can eventually overheat it. Third, the power supply (current to the pump) is critical for maximum performance. Often too thin of wire gauge is used, poor connections, etc, and the pump is misdiagnosed as bad. Another common issue is a heavily contaminated fuel tank clogs the fine wire mesh at the pump's inlet, starving the pump. That's not really a pump failure though. I prefer to install a pre-pump filter in every vehicle regardless.
Click to expand...
The Abarth X1/9 used an external fuel pump but the entire pump is full of fuel so it is submersed. I use a pre fuel filter to prevent any rust or grit from getting into the pump. The issue was that the pump has the Bosch number on it and sold for about $100 USD. I went to car quest and asked for the cost of the new pump and it was about $250 USD, but the count guy said he couldn't tell me where it was made and it may be a knock off that would not last, so I switched to AEM and hope that it will have a longer service life. It is the slots in the pump rotor that wear out of shape. The rollers are fine, the shaft and commutator are fine just the rotor is worn and thus no fuel pressure under boost. My car the boost goes up to 26 PSI and the engine will cut out and then snap back it is like riding a bucking bronco.

TonyK with Bob Martin in the Woodlands Texas
 
Bosch doesn't use rotors in their pumps anymore. That was part of the design changes that took place several years ago when they downsized/streamlined their pump lineup. There is a thread discussing this and I have the official Bosch documents about it somewhere. When I have more time I'll see what I can dig up.
 
It would be interesting to see what changes were made, possibly a better alternative could be installed in my car.

Thanks.

TonyK with Bob Martin in The Woodlands Texas.
 
TonyK said:
It would be interesting to see what changes were made, possibly a better alternative could be installed in my car.

Thanks.

TonyK with Bob Martin in The Woodlands Texas.
Click to expand...
I found my copies of Bosch technical releases for fuel pumps, but they are on my old computer's hard drive so I don't have a easy way to post them here directly. But their fuel pump program went through a major overhaul back in 2009. They reduced the number of EFI pump part numbers significantly, making each one apply to many vehicles by way of adaptors, etc. The internal design also changed to what they call "turbine technology". The rotor was replaced by this "turbine":

elektrokraftstoffpumpe_schnitt_434x300_w734.jpg


One of the features is it does not cause "pulsing" like the older rotor design did (many early German vehicles had a "pulse regulator", basically a can with a diaphragm inside). And the turbine is supposed to provide a more consistent flow with greater efficiency.

If the pump you used was made sometime after 2009 then it is already the turbine design, as all Bosch pumps now are. Similarly, any Bosch pump will now be one of a small number (around 7) base models, with the appropriate adaptors (fittings, connectors, outer sleeves, etc) to fit the application. So buying another one is likely getting the same as what you had. Although the location of the manufacturing facility could be from elsewhere and may make a difference in quality. The package will tell where it was made.
 
DSpieg said:
And if the packaging does NOT provide the country of manufacture, assume it is China.
Click to expand...
Probably a decent assumption generally, but not necessarily true with Bosch products. They have manufacturing facilities all over the world and some may use "generic" Bosch (yellow with red print) boxes with a sticky label indicating the content. And that label may not offer the country of origin in some cases.

dizne-bosch-mercedes-benz-atego-slika-132129094.jpg


This one says "Made in Turkey", but some may not specify. As you can see, they have facilities in places much worse than China.
 
Thanks for the reply, the cross section is totally different than the pumps that I am currently running. The wear factor of this design would be minimal. Do you have a part number for this pump?

Thanks.

TonyK with Bob Martin in the Woodlands Texas.
 
TonyK said:
Thanks for the reply, the cross section is totally different than the pumps that I am currently running. The wear factor of this design would be minimal. Do you have a part number for this pump?

Thanks.

TonyK with Bob Martin in the Woodlands Texas.
Click to expand...
The part number will depend on a couple options. Are you looking for a stock replacement for the year/make/model of the engine you are using? Or do you need a pump for a custom fuel system? Or would something in between be best (e.g. same output but different form factor)? They might all be the same P/N, but I'll have to look them up to see. If it is a stock replacement part then you can search online for the P/N. Or if you want the current replacement for your existing pump, give me that part number and I can look up the cross-reference to the new P/N.
 
Last edited:
Dr.Jeff said:
(many early German vehicles had a "pulse regulator",
Click to expand...

AKA a fuel pressure accumulator.

Bosch is a shadow of its former self. After a few incidents, I refuse to buy their oxygen sensors. And my oxygen sensor experience has really soured me on the whole line. I would rather buy NGK/NTK at this point.

I still have a Bosch 044 motorsport fuel pump for my next project, but when it croaks, I will likely buy a different brand.
 
Longitudinal said:
Bosch is a shadow of its former self.
Click to expand...
I agree. Ever since they sold out to a larger umbrella corporation there's been a lot of changes. And not necessarily for the better. However they do still manufacturer some products in Germany and those are still good quality. So it really depends on the part and where it comes from. Unfortunately it can be difficult to know exactly what you are getting or where it came from.
 
Dr.Jeff said:
The part number will depend on a couple options. Are you looking for a stock replacement for the year/make/model of the engine you are using? Or do you need a pump for a custom fuel system? Or would something in between be best (e.g. same output but different form factor)? They might all be the same P/N, but I'll have to look them up to see. If it is a stock replacement part then you can search online for the P/N. Or if you want the current replacement for your existing pump, give me that part number and I can look up the cross-reference to the new P/N.
Click to expand...
See this link https://www.ebay.com/itm/1935105929...RBpfOjxKR4juJGPEOEwTpIQqtCH5|tkp:BFBMvNqKz_Rg

It is a 044 pump and installation is simple and why it is used. With a lot of work I could modify the stock pump to put into the Fiat X1/9 fuel tank, but everything takes time and adds to the cost of the build.

TonyK at Bob Martin's in Radcliff Kentucky.
 
TonyK said:
See this link https://www.ebay.com/itm/193510592978?hash=item2d0e2151d2:g:5XYAAOSwS4tiYRks&amdata=enc:AQAHAAAA4K0hBd+ueCKGmcm8W8cHsmloB5ohJM/PCuTwievlmY7BYTRnwG4YCKRzFSjkW54R/ggqXMK+3OLGf+N36VPeHawpFfzxaU5TuW8LnDeqYR1fHMnTwntb7t9vFQBm40XKITv5QEM6Ru2Z87aZopD/Mmfbb4Wgxj6XBZTDybLg7J3rno9ZQdIgw2A6T89sVptpVfILJaGAV5o4S6Hd3w0AGzlZvcnqSkL2TCS2Zrv9wm3a7yNq183B1I+QN6dCGvbJxHncQiWdV7mlhkrjRBpfOjxKR4juJGPEOEwTpIQqtCH5|tkp:BFBMvNqKz_Rg

It is a 044 pump and installation is simple and why it is used. With a lot of work I could modify the stock pump to put into the Fiat X1/9 fuel tank, but everything takes time and adds to the cost of the build.

TonyK at Bob Martin's in Radcliff Kentucky.
Click to expand...
The 044 is a high output (high volume and high pressure) standard ("universal") model. It will be the "turbine" type, like all current Bosch pumps. It is popular for lots of big engine/big fuel system applications. Because of its popularity it's one model that is made all over the world. For example the one you linked is made in the Czech Republic. And not all manufacturing locations produce the same quality. Nor do they ask the same price (although sellers can inflate the price so that is not a good measure). Also due to its popularity it is cloned considerably. But if you hold a genuine Bosch and a clone side-by-side the differences are very obvious. If you can find a German manufactured 044 pump it will cost considerably more but will also be the highest quality. However they can be a bit difficult to find.
 
I bought a new Bosch 044 during this season as the "copy 044" suddenly gave up after just three seasons. Luckily this happened just outside the garage when coming home from a 400 km trip. The new Bosch 044 has been redesigned with slightly bigger capacity and is now E85 capable. Only time will tell if it is good or not.
 
I installed one of the new Bosch fuel pumps in my "87 X a couple of months ago. Ever since then I've noticed a new phenomenon - the fuel line pressure bleeds down after a few hours (I have a pressure gauge permanently installed in the engine compartment) and, when I go to start the car, it fires immediately then dies (that's the cold-start injector doing its job), then I have to crank for maybe 3-5 seconds before the engine fires again and keeps running.
I have no gasoline smells, so don't suspect a leak. Could it be that these new-design pumps have a less effective internal check valve than the old ones, such that the new pumps slowly bleed off system pressure back to the fuel tank? Or maybe I have a "slightly defective" pump? (It runs fine once started.) Or maybe a very small fuel line leak that doesn't actually allow gasoline out but does let pressure slowly drop?
 
DSpieg said:
I installed one of the new Bosch fuel pumps in my "87 X a couple of months ago. Ever since then I've noticed a new phenomenon - the fuel line pressure bleeds down after a few hours (I have a pressure gauge permanently installed in the engine compartment) and, when I go to start the car, it fires immediately then dies (that's the cold-start injector doing its job), then I have to crank for maybe 3-5 seconds before the engine fires again and keeps running.
I have no gasoline smells, so don't suspect a leak. Could it be that these new-design pumps have a less effective internal check valve than the old ones, such that the new pumps slowly bleed off system pressure back to the fuel tank? Or maybe I have a "slightly defective" pump? (It runs fine once started.) Or maybe a very small fuel line leak that doesn't actually allow gasoline out but does let pressure slowly drop?
Click to expand...
The check valve on Bosch pumps is actually externally mounted. If you look at the exiting end of the pump you'll see a fitting screwed onto the nose of the pump body. Then there is another fitting screwed onto the end of that first fitting, with the banjo or barb connection to your fuel line. The first fitting (directly on the nose of the pump) is the check valve.

You can easily remove and test the check valve. If it's not holding pressure then it is easy to replace it. However I highly doubt it is the check valve. They are not prone to failing. More likely you have a leak somewhere after the check valve, even though you don't smell fuel. It could even be a injector leaking so the fuel is going inside the engine where you won't smell it (a fairly common occurrence).

This is the check valve in red:
titanmotorsports_2225_152497617__39754__47610.jpg
 
You must log in or register to reply here.
Back
Top