1986-88 Bosch CIS K-Jetronic injected Esprit specific items - Page 5 - LotusTalk - The Lotus Cars Community
 9Likes
Reply
 
LinkBack Thread Tools Display Modes
post #81 of 258 (permalink) Old 03-26-2014, 01:00 PM
Registered User
 
Join Date: Feb 2014
Location: Seattle, Washington
Posts: 260
EFI conversions are getting better and less expensive all the time. Gone are the days of confusing and crude software programming, one-vendor monopoly parts supply, etc. There are great systems available for 4, 6, 8 cylinder cars for reasonable cost and complexity.

Bosch CIS is a good and reliable system, but it's far from optimized for maximum performance. If squeezing a lot more hp out of 4 cyl Lotus is your thing then it's very difficult to do without moving to a full EFI set up.

If you need to keep it simple....and you want big hp....then better off considering something like a small block Ford with a Holley like this.
Attached Images
 
Beerman is offline  
Sponsored Links
Advertisement
 
post #82 of 258 (permalink) Old 03-26-2014, 06:51 PM
Registered User
 
Join Date: Nov 2009
Location: New Jersey
Posts: 3,115
Quote:
Originally Posted by Beerman View Post
EFI conversions are getting better and less expensive all the time. Gone are the days of confusing and crude software programming, one-vendor monopoly parts supply, etc. There are great systems available for 4, 6, 8 cylinder cars for reasonable cost and complexity.

Bosch CIS is a good and reliable system, but it's far from optimized for maximum performance. If squeezing a lot more hp out of 4 cyl Lotus is your thing then it's very difficult to do without moving to a full EFI set up.

If you need to keep it simple....and you want big hp....then better off considering something like a small block Ford with a Holley like this.
I would be careful trying to get more HP through the Citroen box which is what is used in the '88's. I agree it is getting cheaper and easier to install an EFI set-up but it will still be less expensive to get the K-Jet system going and optimized. The biggest reason to stay "stock" is for service. No Lotus shop is going to want to service the car and if they do you had better have "Deep Pockets". The absolute worst thing you ever want to do is buy a car that is heavily modified and not be able to work on it yourself. Any shop willing to work on the car is going to be spending a lot of your money learning about it and guessing what to do.
David Teitelbaum
jtrealty is offline  
post #83 of 258 (permalink) Old 03-26-2014, 09:00 PM Thread Starter
Integrator
 
MRDANGERUS's Avatar
 
Join Date: Aug 2010
Location: N-East Central USA
Posts: 2,656
Garage
BEWARE OF SEAFOAM

Be very careful using Seafoam additive in 1986-1988 Bosch CIS injected Cars.
High concentration of this product will damage the diaphragm in your Bosch Fuel Distributor.
For many years, now, the diaphragms are made of some kind of plasticized fabric, not steel.
Best solution: not use it at all.

At least there is a kit on ebay to fix the problem
Attached Images
 

Last edited by MRDANGERUS; 03-27-2014 at 06:40 AM.
MRDANGERUS is offline  
 
post #84 of 258 (permalink) Old 03-27-2014, 04:49 AM
Registered User
 
Join Date: Nov 2009
Location: New Jersey
Posts: 3,115
Quote:
Originally Posted by MRDANGERUS View Post
Be very careful using Seafoam additive in 1986-1988 Bosch CIS injected Cars.
High concentration of this product will damage the diaphragm in your Bosch Fuel Distributor.
Best solution: not use it at all.
It is never a good idea to use any product contrary to the directions. Used properly, Sea Foam should be OK. The gasket in the Fuel Distributor is made of steel so I don't see how you can damage that without damaging everything. You should not have to use any additives in the fuel anyway if the car is being used. And if it is not being used all of the fuel should be removed. Modern fuel has plenty of additives in it already. About the only fuel additive I recommend is Techron anyway. You should not have to use it often and only put it into a full tank of fuel and use it up right away. Works good to clean the fuel injectors to keep the spray pattern good.
David Teitelbaum
jtrealty is offline  
post #85 of 258 (permalink) Old 03-27-2014, 05:00 AM
Registered User
 
greentengu's Avatar
 
Join Date: May 2013
Location: Quakertown, PA
Posts: 183
Hmmmm.... The P.O. of my car used to pour cans of a "BG 44k" to "Rapidly [remove] Harmful Engine Deposits" from the engine. I even have copies of letters he sent (or, properly, his secretary sent) asking a dealer to send him more cans of the stuff (with, oddly, no mention of payment). When I took ownership I even got a box filled with '86 bits and baubles, including several cans of this stuff. I can only wonder if it had any harmful effects.

However, I would ask, exactly what does Seafoam do to the CIS distributor? Also, what is the source of this claim? The Vortex? Their CIS-only sub-forum is fairly authoritative. In fact, such subforums certainly could benefit this forum (CIS, carb, EFI). But that is a topic for another day.

Last edited by greentengu; 03-27-2014 at 05:14 AM.
greentengu is offline  
post #86 of 258 (permalink) Old 03-27-2014, 08:35 AM
Registered User
 
Join Date: Nov 2009
Location: New Jersey
Posts: 3,115
Many of the fuel distributors use metal gaskets, that kit shown has a rubber gasket. Too much of a good thing can destroy rubber, even the stuff they pass of as gasoline nowadays. Years ago many people religiously used cans of "DRY GAS". It's purported purpose was to "dissolve" any water in the fuel system and allow it to burn along with the gasoline. Today we now know it as Ethanol (alcohol) and it is liberally mixed into the gas to dilute it and "oxygenate" it. Putting in even more "stuff" as an additional additive can cause problems with the already high proportion of Ethanol. Especially if you put in more than is recommended. Most companies warn you to put their additive in with a full tank of fuel and burn it all up quickly and then refill with only gasoline. That way there is less chance of the stuff attacking the components of the fuel system, only the dirt. You should also use any additive sparingly, some can damage the catalytic convertor is used too often.
David Teitelbaum
jtrealty is offline  
post #87 of 258 (permalink) Old 04-09-2014, 09:43 PM Thread Starter
Integrator
 
MRDANGERUS's Avatar
 
Join Date: Aug 2010
Location: N-East Central USA
Posts: 2,656
Garage
X180 FUEL TANKS

If you decided to replace old fuel tanks with custom made alloy parts, it may be an excellent time to think about incorporating some improvements.

I’ve been curious why on 86-88 CIS K-Jetro cars Lotus attached FD fuel return line to the right tank.
Such config keeps the same batch of fuel circulating over and over making it go “sour” and warmer every time it completes the loop.

IMO, one can reduce fuel aeration and temp rise by attaching the return line to the left tank. Cool fuel in the LH tank would mix with somewhat warmer return charge, de-aerate and flow trough the cross pipe directly to the right tank sump (from where the external pumps get petrol). Right tank would act only as a leveling vessel providing steady surface for the level sending unit.

Last edited by MRDANGERUS; 04-10-2014 at 09:03 PM.
MRDANGERUS is offline  
post #88 of 258 (permalink) Old 06-28-2014, 08:31 AM Thread Starter
Integrator
 
MRDANGERUS's Avatar
 
Join Date: Aug 2010
Location: N-East Central USA
Posts: 2,656
Garage
I thought, it would be useful to list some CIS related threads:
So, here it goes:

https://www.lotustalk.com/forums/f164...00-rpm-238753/

https://www.lotustalk.com/forums/f164...e-88-a-116630/

https://www.lotustalk.com/forums/f164...-level-226826/

https://www.lotustalk.com/forums/f164...tronic-113188/

https://www.lotustalk.com/forums/f164...ration-200113/

http://www.lotusespritturbo.com/Lotus_Esprit_Turbo.htm

http://www.hagerty.com/price-guide/1988-Lotus-Esprit


https://www.lotustalk.com/forums/f164...-issue-178313/

https://www.lotustalk.com/forums/f164...-start-170217/

https://www.lotustalk.com/forums/f164...e-help-173506/

https://www.lotustalk.com/forums/f164...-relay-172361/

https://www.lotustalk.com/forums/f164...riving-147921/

https://www.lotustalk.com/forums/f164...riving-135769/

https://www.lotustalk.com/forums/f164...gotten-146273/

https://www.lotustalk.com/forums/f164...passed-100925/

https://www.lotustalk.com/forums/f164...please-123410/

http://www.thelotusforums.com/forums...ment-of-boost/

http://www.thelotusforums.com/forums...-owners-unite/

http://www.thelotusforums.com/forums...rbo-too-laggy/

http://www.thelotusforums.com/forums...ons-and-specs/

http://www.thelotusforums.com/forums...8-x180-esprit/

http://www.thelotusforums.com/forums...of-e15-petrol/

http://www.thelotusforums.com/forums...num-gas-tanks/

http://88lotusespritturbo.info/Detai...provements.htm

http://www.espritfactfile.com/Parts.html

Last edited by MRDANGERUS; 07-06-2014 at 08:51 AM.
MRDANGERUS is offline  
post #89 of 258 (permalink) Old 07-01-2014, 05:44 AM
Wingless Wonder
 
carbuff's Avatar
 
Join Date: Jun 2004
Location: In the Back of your Mind
Posts: 5,352
Garage
^^ Hey, thanks for assembling those in one place, Mr. D!

Atwell Haines
'88 Esprit
Succasunna, NJ USA


"Not all angels have wings." - Turbo R
carbuff is offline  
post #90 of 258 (permalink) Old 07-06-2014, 08:57 AM Thread Starter
Integrator
 
MRDANGERUS's Avatar
 
Join Date: Aug 2010
Location: N-East Central USA
Posts: 2,656
Garage
MRDANGERUS is offline  
post #91 of 258 (permalink) Old 07-06-2014, 10:36 AM
Registered User
 
Join Date: Nov 2009
Location: New Jersey
Posts: 3,115
Quote:
Originally Posted by MRDANGERUS View Post
If you have anything CIS or 86-88 specific, please add to the list!
From your list, the way you put it, it would seem like it is a small miracle the Bosch system works at all! With a little maintenance it is a simple, rugged, and reliable system with some caveats. It doesn't store well and is not very tolerant of dirt. It uses Lucas electronics and wiring which can be problematic. It doesn't require a lot of complicated and expensive service equipment. One of it's biggest failings is that most mechanics who attempt to work on it do not understand it and therefore do not know how to properly troubleshoot it. One of the very best resources for information, besides the service manual, is;

Bosch Fuel Management & Engine Management
by Charles O. Probst, SAE

David Teitelbaum
jtrealty is offline  
post #92 of 258 (permalink) Old 07-07-2014, 08:39 AM Thread Starter
Integrator
 
MRDANGERUS's Avatar
 
Join Date: Aug 2010
Location: N-East Central USA
Posts: 2,656
Garage
Yes, this book is the best!

All fuel systems are sensitive to debris/contamination, no exceptions.

The most egregious FUBAR is an omission of the in-tank strainer to protect the pumps on Bosch injected cars.

Definitely vacuous thinking !

Last edited by MRDANGERUS; 07-09-2014 at 01:31 PM.
MRDANGERUS is offline  
post #93 of 258 (permalink) Old 07-09-2014, 09:47 AM Thread Starter
Integrator
 
MRDANGERUS's Avatar
 
Join Date: Aug 2010
Location: N-East Central USA
Posts: 2,656
Garage
STRAINER INSTALLATION

Since there is not much room between the rocker inner and primary pump inlet, I mounted the strainer in a vertical position.
I started with fat EARL's 80 um strainer, but replaced it later with much thinner 30 um JAZ filter wit 10AN fittings. I used PEX elbows and crimp rings to save some room.
The screw-in contraption is a magnetic particle trap containing extra strong Neodymium button magnets. I added it because JAZ was loading up too fast with rust and to clean it out I had to take the whole "loop" off the car too often.
The trap cleans out quite easy, just by unscrewing the large hex cap.
Attached Images
         

Last edited by MRDANGERUS; 07-09-2014 at 10:26 AM.
MRDANGERUS is offline  
post #94 of 258 (permalink) Old 07-09-2014, 11:12 AM
Registered User
 
greentengu's Avatar
 
Join Date: May 2013
Location: Quakertown, PA
Posts: 183
Outstanding, detailed pics. The addition of the magnets is seriously cool; what a good way to help filter metallic particles.

Can you give the specs on the JAZ filter? And, why did you switch? I remember that the Earl's filter--which is featured on a thread somewhere--was thought to be a panacea, but then it clogged up to easily, which could have led to a seriously lean condition (and eventual engine damage associated with lean conditions). How does the JAZ filter differ from the Earls, besides in dimensions?

Oh--why is that piece of black tape wrapped around the curve? To protect it from rubbing against/chafing itself against other parts?

As usual, cheers!

Scott
greentengu is offline  
post #95 of 258 (permalink) Old 07-09-2014, 01:16 PM Thread Starter
Integrator
 
MRDANGERUS's Avatar
 
Join Date: Aug 2010
Location: N-East Central USA
Posts: 2,656
Garage
Earl's filter has a small flat stainless steel mesh disc, whilst JAZ has a conical sintered metal filtering element (4-5 times larger surface). JAZ lasts longer and it is easier to clean. Look on ebay for the part with 10AN ends.
Our cars are plagued by tanks rusting internally (sooner or later). After the coating flakes off the shear volume of rust particles is overwhelming. Change fuel filter often, (Purolator F64857), at least untill you replace steel tanks with aluminum ones. Always, cut it up with a can opener and enjoy the view, LOL.

The black tape and foam prevents the top of the loop from rubbing/hitting body and other components (it is pretty tight up there).

Last edited by MRDANGERUS; 07-10-2014 at 07:40 AM.
MRDANGERUS is offline  
post #96 of 258 (permalink) Old 07-19-2014, 06:16 PM
Registered User
 
88LotusEsprit's Avatar
 
Join Date: Jan 2011
Location: Canada
Posts: 43
I cannot express how much I hate this Bosch injection system, such crap in my opinion. If it was good, it wouldn't be the longest thread or most written about subject on these cars.
Sorry, my opinion, but Lotus really blew it on this decision as well as a few other decisions on the 88 model year.

Cheers,
88 Lotus Esprit


88 Esprit
03 Esprit
06 Gallardo SE
88LotusEsprit is offline  
post #97 of 258 (permalink) Old 07-19-2014, 11:20 PM
Moderator
 
sleekgt's Avatar
 
Join Date: Aug 2011
Location: San Jose, California
Posts: 3,711
Garage
Quote:
Originally Posted by 88LotusEsprit View Post
I cannot express how much I hate this Bosch injection system, such crap in my opinion. If it was good, it wouldn't be the longest thread or most written about subject on these cars.
Sorry, my opinion, but Lotus really blew it on this decision as well as a few other decisions on the 88 model year.
Curious to the specific parts about Bosch CIS you don't like? I've had a car with Bosch CIS (Scirocco) for over 100K miles without any problems.

That's why I picked an Esprit with Bosch CIS - familiarity and reliability. I've got 61K miles on my 88 (31K I put on myself in 31 months) and the Bosch CIS (even at 26 years old) has been bulletproof.

Lastly, my wife's friend has an 83 Scirocco with Bosch CIS-E with 347K miles (yes, three hundred forty seven thousand) with the ORIGINAL Bosch CIS injectors, lines, etc - pumps may have been replaced at 180K). It's still driven to this day AND passes stringent California smog regulations.

Sure, other people may have had Bosch CIS problems, but it's not due to any inherent design weakness. If there is a vacuum leak, it can be a bear to diagnose if you're not familiar with it. And unlike electronic fuel injection, it doesn't easily take to mods (MRDANGERUS is the exception here )

The main problems in 2014 are:

1. Key parts are hard to find now
2. Most people don't want to bother to learn how an obsolete FI system works
3. Not many people are familiar with diagnosing Bosch CIS - they're all old (like me) or dead

Eddie B
87 Esprit 'SLEEK GT'
sleekgt is online now  
post #98 of 258 (permalink) Old 07-20-2014, 09:04 AM Thread Starter
Integrator
 
MRDANGERUS's Avatar
 
Join Date: Aug 2010
Location: N-East Central USA
Posts: 2,656
Garage
Quote:
Originally Posted by 88LotusEsprit View Post
I cannot express how much I hate this Bosch injection system, such crap in my opinion. If it was good, it wouldn't be the longest thread or most written about subject on these cars.
Sorry, my opinion, but Lotus really blew it on this decision as well as a few other decisions on the 88 model year.
My Canadian friend,
you are entitled to your opinion, but you are wrong all day long.

Over 1.6 million of cars were equipped with CIS system, including MB, BMW, Ferrari, Lamborghini, Maserati, Bentley, etc,etc.

This thread is long and comprehensive by design.

It serves several purposes:
1. It supposed to be a quick immersion / learning course for the new 86-88 Bosch CIS car OWNERS.
2. It compiles all pertinent CIS information in one place
3. It provides support, education and assistance to CIS car owners

What it is NOT:
1. A whiner/complainer/malcontent soap box.

Last edited by MRDANGERUS; 08-07-2014 at 06:52 AM.
MRDANGERUS is offline  
post #99 of 258 (permalink) Old 08-07-2014, 07:28 PM Thread Starter
Integrator
 
MRDANGERUS's Avatar
 
Join Date: Aug 2010
Location: N-East Central USA
Posts: 2,656
Garage
CIS FUEL PUMPS

If your pumps suddenly stopped working, you'll need this diagram.

First, check all the connections.
Often, the female spade terminals get loose or get pushed down/out of the relay base. OE terminals have no protective coating and they corrode prematurely.
Pump relays get activated when terminals 85 get the ground. There are several safety features preventing that; inertia switch and engine overspeed module have to be ON.
Notice, that overboost relay is NC (30/87a) until its coil is activated (across terminals 85/86) by an overboost safety switch and low coolant sensor.

Old relays"Made in W. Germany" should be replaced by modern, (suppressed) high quality parts.

NOTE: This is 1988 ET diagram!
87 and prior may be slightly different, see post #100, below.
Attached Images
 

Last edited by MRDANGERUS; 08-09-2014 at 08:22 PM.
MRDANGERUS is offline  
post #100 of 258 (permalink) Old 08-09-2014, 02:02 PM
Registered User
 
Autocross7's Avatar
 
Join Date: May 2013
Location: Alabama
Posts: 175
Regarding the above diagram... we did discover looking at issues with the 87' vs 88' that this is different between the two cars... Sorry, I do not have an 87' to post up.

Just note that it is different - and maybe somebody has an 87' diagram to post?
Autocross7 is offline  
Sponsored Links
Advertisement
 
Reply

  LotusTalk - The Lotus Cars Community > Lotus Discussions > Lotus Esprit

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the LotusTalk - The Lotus Cars Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome