3.14 Differential Refurb #3

Finished off painting the diff and cleaning up the side beading housings, fitted some new high tensile bolts to hold the back plate and side fixings in place.

Decided to fit an LSD while the diff is apart. Spoke to Quaife and ordered a QDF15Z helical LSD for a 7 inch Sierra diff. Dismantled the original open diff and removed the crown wheel, fitted the crown wheel to the new LSD and torqued up the bolts. The crown wheel looks like new so that's a bonus. I ordered a new set of bearings which I will get pressed on to the shafts tomorrow at my local garage.

IVA Failure #2

Gave Chris a chase today to get an update on progress with my car. I have had various conversations with MNR since my car failed the IVA.

The brake balance issue has been fixed by changing the setting on the remote adjuster. The noise issue has been somewhat perplexing. Marc borrowed Damian's noise level meter and in the workshop the reading at 7000rpm was 95db from the exhaust, however the reading at the IVA test was 104db with a calibrated meter. Marc has added an extra baffle to the exhaust in an attempt to make things quieter.

To try and help out, I bought a noise level meter from Maplin and sent it up to MNR to get another reading. As a precaution Marc agreed to order some sound proofing to fit to the engine bay and also to connect a flexi hose to the air intake of the stock airbox. The idea of connecting a hose to the air box came from a friend of mine with a Caterham, apparently Caterham route the inlet of their airbox on the R500 away from the induction area. The ducting moves the induction noise away from the engine and to the location of the outlet. 

As the noise level reads an acceptable level and is under 99db the car is being booked in for a re test. Hopefully I will get a better result.

 

Daytuner Dyno Results

Damian sent over a copy of the Dyno plot from his mapping session yesterday. The output of the mapping session gave 171 wheel hp and 99 ft/lb torque, this seems ok but is slightly less than expected.

In talking to Damian there are a few issues with the engine, the problem with the rings letting by is causing a loss of power and control of combustion at the top end of the rev range. I'll most likely swap the pistons out when I Supercharge the engine next year.

Unfortunately there is also an issue with the engine smoking badly on overrun, Damian feels it may be the valve guides that need replacing. I'll see how bad it smokes when I get it back and remove the head for inspection if need be. I hope that this is not the case as guide replacement is expensive.

The final issue is that the counter balancer has been removed which makes the engine vibrate quite badly without it. This is apparently often removed and thought to give more power, but is not really proven. These are quite cheap on eBay, so I can get one to try it out to see if it makes things better.

All in all, I guess that I have learnt a lesson that there is no such thing as a hardly used race engine, always assume that they have had a hard life and expect to have to pay for a refresh. In hindsight, I would have been better off with a stock engine for my build.

Cleaning Parts By Electrolysis

Decided to try cleaning the prop shaft flange from the diff by electrolysis. Found a guide on the internet and gave it a go with good results. Would have been great to use this method for refurbing parts during my build.

The chemistry bit....

Electrolysis involves passing an electric current through an electrolyte; the result is a movement of charged ions from one electrode to the other. In this process, the rust (Fe2O3) is chemically converted to iron, releasing oxygen and hydrogen. Electrolysis works best with iron, but can work with any metal that can conduct electricity. It should be noted that some metals, like aluminium, will disintegrate faster than others.

CAUTION: This project can be dangerous; take all precautions to ensure your safety.

If the item has rubber parts, then this process may harden the rubber or leave the surface rather sticky.

Things You'll Need:

• Plastic bucket or similar plastic container.
• Battery charger (with 'Boost' mode) 
• Sodium Carbonate / Washing Soda / Soda Ash
• White vinegar 
• Safety glasses
• Safety gloves
• Scrap Copper
• Wire Brush
• Paper Towel

Step 1.

Add 1/3 cup Sodium Carbonate to 100ml White vinegar (Lemon Juice also works) in a cup. Mix into a paste, adding warm water as necessary. 

Caution: this mixture will froth so wear safety glasses and gloves. 

It is the current that cleans, not the solution, so making a more concentrated solution does nothing.

Step 2.

Using a wire brush, remove any loose rust from the item to be cleaned.

Step 3.

Put on the rubber gloves and goggles; as this paste is toxic and really irritates the skin. Using a paper towel, cover the item in the paste from Step 1 and leave to stand for 15 minutes.

Step 4.

Fill a bucket or similar plastic container with 4.5litres of water (warm is better - it helps the paste dissolve more quickly).

Step 5.

Connect a piece of clean scrap copper (rebar) to positive lead (anode) from a 12v battery charger (The red lead from the battery charger is the positive node.) Clamp it into place ensuring that it does not touch the side or bottom of the bucket. The rebar is a sacrificial anode will corrode away. Therefore ensure the charger's clamp does not come into contact with the water. 

A Stainless Steel rebar may produce better results, but it will release a highly toxic gas (Chromium). This gas is not just very irritating to the skin it has also been directly linked to lung cancer.

Step 6.

Connect the negative lead (cathode) from the DC source to the material that needs to be cleaned. The negative terminal will not corrode like the positive, however the solution is still aggressive and therefore it may be a good idea to insert a short length of thick wire between the item and the charger's negative clamp.

NB. The item will clean more effectively, if a minimal amount is resting against the bottom of the bucket. It may be good to prop it up with something non-conductive and scrap.

Step 7.

Double-check all connections, making sure nothing is touching; the electrodes should not be touching each other, nor should they be touching the sides or the bottom of the bucket. Make sure you have enough electrolyte solution to cover the part being cleaned.

Step 8.

Turn on the power. Bubbles will immediately form on the surface, especially around the positive anode. This is mostly hydrogen (from the cathode) and oxygen (from the anode) being released. Remember, the water is now 'live' so don't stick your fingers in!

Do not breath this gas! This gas is also explosive, so not not smoke! It is best to do this outside. 

 NB. If you charger has not got a high power 'Boost' mode, you could use a fully charged car battery.

Step 9.

Turn off the Power!

Cleaning a Diff flange took around 12 hours. The item was removed regularly and dressed with a wire brush. This seemed to speed up and improve the cleaning process. To re-use the liquid, remove the electrodes and leave to stand for an hour. Carefully drain off the fluid and dispose of the debris in the bottom. Give the electrodes a good scrub with the wire brush. The fluid can be re-used a few times before it becomes too acidic.

3.14 Differential Refurb #2

Dismantled the differential, removed the side covers and internal planet gearing. Managed to remove the bearing housings without breaking the teeth. Ended up heating the casing with a blow torch and the bearing houses eventually moved with a tool from eBay and a breaker bar.

Undercoated the diff with Hamerite primer and then painted a first coat with silver metal paint. Soaked the bearing housings in de greaser overnight and will clean later. More coats of paint tomorrow.

SBD Throttle Bodies & 690cc Injectors

Chatted with Marc on Friday and agreed that as Damian will be away on holiday soon for a month, the best plan would be to get my car mapped for performance this week and then sort the IVA afterwards.

The IVA issues that are to be fixed are the brake balance and the noise at 102.4db and needs reducing to 99db at 7680rpm (based on 3/4 of 10200rpm). Marc feels confident to sort the noise with a slight change to the silencer and and adjustment to my airbox.

In the meantime I went up to MNR today and fitted my SBD 50mm throttle bodies, 690cc injectors and a itg foam filter. I also fitted the flat shifter blipper and a new throttle cable. The car will then be taken to Damian at Daytuner for setup. As the SBD throttle bodies use aluminium velocity stacks they will not work with the standard airbox, have fitted a basic itg until I find at a better solution. 

IVA Failure #1

Marc Norden of MNR took my car for it's IVA test first thing this morning at the Beverly testing station. As I had not heard anything by early afternoon, with anticipation I decided to chase Chris to see if there was some news. 

Disappointingly Chris told me that my car had failed. He went on to say that this was due to noise levels and also that the brake balance was out. 

After the failure, I am now waiting to see what solution is proposed and when the re test will be. 

3.14 Differential Refurb #1

Managed to get a 3.14 diff from eBay for a good price. I plan to clean it up and then to use it as a spare, maybe in time get an LSD fitted.

First job was to remove the back plate to check that it actually is a 3.14 and also to look at the crown wheel, pinion and planed gears for wear. The bolts on the back plate eventually moved with the exception of one which I broke a hex bit on. I ground the head off and then removed the back plate.

It is a 3.14, all looks fine and the gears all look tidy. 

The diff was really dirty, caked in mud and grease. First I jet washed off the mud, then applied de-greaser and jet washed again. Next I cleaned the casing with wire brushes to get ready for paint.

Removed the diff flange, used a gear puller to remove the flange from the splined shaft. The diff flange looks heavily rusted and needs a good clean. Read somewhere about electrolysis cleaning so might have a go to clean it up.

Masked off the edges of the diff and ready for paint.

Some More Bits

While the car has been away at MNR I have been getting a few bits ready to be installed after it's been registered. Seeing Chris's car really spurred me on and gave me some ideas.

I've ordered a pair of Tillett carbon B6F seats similar to the ones Chris has in his grey car. These are due in about 2 weeks, I also have a rear diffuser to fit that I've had for a while. 

Still need to order an aero screen and get some 0.7mm carbon for the rear boot lid to replace the carbon effect one fitted.

On the engine front I have the SBD throttle bodies, 690cc injectors, flat shifter blipper kit and a pipercrosss filter to go on before the final mapping session with Daman. Originally I planned to fit these later, but if I get it done now I will save a mapping session. 

Getting ready for IVA at Daytuner #2

Spoken to Damian today for an update, he has now swapped over the cams for a standard set and shimmed them for the correct clearances. The emissions are now where they need to be for the IVA test.

I'm glad it's sorted now, will get the car fully mapped for performance at a later date.