Search found 516 matches

by jagwit
Sun Jul 12, 2020 3:57 pm
Forum: Series 3
Topic: V12 Overheating: The contributing factors
Replies: 13
Views: 813
South Africa

Re: V12 Overheating: The contributing factors

Thermostat rating should not be on the list. This is the temperature that the thermostat starts to open, It seems to me you are wrong on this statement Colin. I tested two brand new tstats from different manufacturers. One was 74C and the other 82C: The 82C starts to open at 72C and is fully open b...
by jagwit
Sun Jul 12, 2020 2:30 pm
Forum: Series 3
Topic: V12 Overheating: The contributing factors
Replies: 13
Views: 813
South Africa

Re: V12 Overheating: The contributing factors

Thermostat rating should not be on the list. This is the temperature that the thermostat starts to open, hotter ratings are for faster warm-up, that is all. Respectfully, nope. Temp rating determines the point around which the thermostat will regulate. It would be correct to accept that it would be...
by jagwit
Sun Jul 12, 2020 7:59 am
Forum: Series 3
Topic: V12 Overheating: The contributing factors
Replies: 13
Views: 813
South Africa

Re: V12 Overheating: The contributing factors

If you have overheating issues, a good starting point is to know absolutely that it is not a design problem, that the Jaguar design is about as good as it possibly could be. I fully agree Colin. I have gone on record many times stating that the std fans ARE good enough!! Modifying thermostats belon...
by jagwit
Sun Jul 12, 2020 7:44 am
Forum: Series 3
Topic: V12 Overheating: The contributing factors
Replies: 13
Views: 813
South Africa

Re: V12 Overheating: The contributing factors

MarekH wrote:
Sat Jul 11, 2020 9:08 pm

A retarded ignition (malfunctioning distributor) can also be added to the list.
Thank you Marek! Added to 1st post.

This prompted the thought that overfuelling should also be added.
by jagwit
Sat Jul 11, 2020 3:31 pm
Forum: Series 3
Topic: V12 Overheating: The contributing factors
Replies: 13
Views: 813
South Africa

V12 Overheating: The contributing factors

Herewith a concise summary of the most relevant contributing factors to the V12 overheating / running hot (if I left something important out, I'll add it to this 1st post). Where needed, further expounding is offered further down. SUMMARY (This section is again split into PRIMARY and SECONDARY consi...
by jagwit
Sun Jul 05, 2020 2:15 pm
Forum: Series 3
Topic: Engine tone beating under acceleration
Replies: 1
Views: 261
South Africa

Re: Engine tone beating under acceleration

Check the engine mountings. Particularly the one on the RHS. This caused the rhs air filter housing to be touching the body frame.
by jagwit
Mon Jun 29, 2020 2:54 pm
Forum: Series 3
Topic: Setting the carburettor jet distance below the bridge
Replies: 8
Views: 714
South Africa

Re: Setting the carburettor jet distance below the bridge

Doddsy wrote:
Sat Jun 27, 2020 8:15 pm
I have since been messing with the carburettor set up and balancing to try and get the engine running better.
What ignition system do you have? Without impeccable ignition (OPUS does NOT qualify), you can tune till the cows come home.... :questionmarks:
by jagwit
Mon Jun 29, 2020 8:18 am
Forum: Series 3
Topic: Not all cylinders firing...
Replies: 7
Views: 588
South Africa

Re: Not all cylinders firing...

Previous owner of my current S3 purchased a new OPUS ferrite disc from SNG as well as a REOPUS. The car refused to run well. With his electronic background and my PICOSCOPE he started looking into things.... and found as follows: 1. Not all the ferrite rods were located on the same radius from the c...
by jagwit
Mon May 11, 2020 7:45 pm
Forum: Series 3
Topic: V12 ECU
Replies: 70
Views: 10100
South Africa

Re: V12 ECU

Excellent news!

Congratulations Michel!
by jagwit
Sun May 10, 2020 7:28 pm
Forum: Series 3
Topic: V12 ECU
Replies: 70
Views: 10100
South Africa

Re: V12 ECU

:wow:

:bouncyyellow:

:lol:

:drinkingcheers:

:swerve:

Its always good to find the "smoking gun" or, in this case...... the missing pipe.
by jagwit
Sun May 10, 2020 8:50 am
Forum: Series 3
Topic: V12 ECU
Replies: 70
Views: 10100
South Africa

Re: V12 ECU

I'm looking now for a new Marelli ignition ECU. Why? I have not seen anything you wrote to suggest the Marelli ignition ECU is faulty. Perhaps you meant "an EFI ECU for a Marelli car"? Thanks for your input Marek!! I did not know that the pressure sensor output on the Jag ECU is resistive (like an ...
by jagwit
Mon May 04, 2020 2:11 pm
Forum: Series 3
Topic: V12 ECU
Replies: 70
Views: 10100
South Africa

Re: V12 ECU

I'also tried to put a vacuum with a syring on the tube going to the ECU. Nothing change. Nothing happen. I will open the ignition ECU to see what's going on. This is a positive finding. When you say "Nothing change. Nothing happen.", are you saying that when applying vacuum, the ECU is not changing...
by jagwit
Sat May 02, 2020 12:28 pm
Forum: Series 3
Topic: V12 ECU
Replies: 70
Views: 10100
South Africa

Re: V12 ECU

Another idea.... Fit another longer pipe to the ECU vacuum port, such that its easy to apply vacuum to it with some vacuum tool (like a 60cc syringe). Start the engine and apply vacuum with the tool. The idea is just to see if applying the vacuum makes a difference to how the engine runs. If doing s...
by jagwit
Thu Apr 30, 2020 2:22 pm
Forum: Series 3
Topic: V12 ECU
Replies: 70
Views: 10100
South Africa

Re: V12 ECU

The 4.47 does not bother me. It is not hugely different from mine. The 0.6k also does not bother me because that value is determined by how the pot is locked to the base plate with those 3 little bolts (where the adjustment SHOULD be made). To set the pot do as follows: 1) Disconnect the two long th...
by jagwit
Wed Apr 29, 2020 6:19 pm
Forum: Series 3
Topic: V12 ECU
Replies: 70
Views: 10100
South Africa

Re: V12 ECU

On the doc from R Bywater to get an XJS engine used in the E type he indicates that this switch brings 15% more @ full throttle. If mine gives not a clear 0 , it may bring these 15% more, dont you think so ? One would have to measure that on a car but I don't think the 20Ohm will be a problem. That...
by jagwit
Wed Apr 29, 2020 6:17 pm
Forum: Series 3
Topic: V12 ECU
Replies: 70
Views: 10100
South Africa

Re: V12 ECU

I don't have a a full load vacuum switch, sorry.

The spare throttle pot I have, seems to be in perfect working order! Surprise!!
I measure 3.62 kOhm between Yellow and Green.
Between Yellow and Red, it starts at 430 Ohm and gradually goes up to 3.78 kOhm as you turn the rotor.
by jagwit
Wed Apr 29, 2020 5:54 pm
Forum: Series 3
Topic: V12 ECU
Replies: 70
Views: 10100
South Africa

Re: V12 ECU

Aha, the full load vacuum switch is a switch yes. I would expect it to be "0" Ohm when closed and infinity when open. I think I have a spare and will measure mine. But anyway, no, this switch only brings about a slight enrichment of the mixture. I can not see that it can be the cause of your problem...
by jagwit
Wed Apr 29, 2020 5:21 pm
Forum: Series 3
Topic: V12 ECU
Replies: 70
Views: 10100
South Africa

Re: V12 ECU

Philip, is the throttle valve a simple switch ? When I turn the power on, all the injectors do a on/off. Is this normal ? Next restauration I will try to an Electric E type! :bigrin: When you say "throttle valve", I presume you are referring to the throttle potentiometer? It is NOT a switch. It is ...
by jagwit
Mon Apr 27, 2020 1:28 pm
Forum: Series 3
Topic: V12 ECU
Replies: 70
Views: 10100
South Africa

Re: V12 ECU

1) I confirm that the small hose is connected on both side. However I’m wondering if I’ve not bent it during the re routing from the wiring. I’ll check this. 2) I’ll verify the one dedicated to the EFI. I do have fit a new one at the rear from the right water rail because as as you know, the E Type...
by jagwit
Mon Apr 27, 2020 9:39 am
Forum: Series 3
Topic: V12 ECU
Replies: 70
Views: 10100
South Africa

Re: V12 ECU

Another thing Michel When an engine is running as rich as yours, plugs can "foul" (become carbon covered, which makes a dead plug) very quickly. I'm talking minutes now!!! Then, even if you fix the fuelling issue, the engine will not run or it will run badly, but now because of fouled plugs. So, I'm...