HEAVY DUTY D/R TIMING CHAIN CONVERSION KIT FOR NISSAN NAVARA D22 D40 YD25DDT YD25DDTI 16V 2.5L I4

HEAVY DUTY D/R TIMING CHAIN CONVERSION KIT FOR NISSAN NAVARA D22 D40 YD25DDT YD25DDTI 16V 2.5L I4Timing chains are known to stretch on the YD25 engine, even at a very low distance travelled. This kit has been developed to ensure the problem is solved once and for all and there is no need to worry about it ever again. About The Kit: Chains: We offer customers a choice between genuine Nissan and German Iwis chains. Iwis chains cannot be used with genuine or aftermarket sprockets (other than ours) due to differences in pitch and width. We supply

Timing chains are known to stretch on the YD25 engine, even at a very low distance travelled. This kit has been developed to ensure the problem is solved once and for all and there is no need to worry about it ever again.

About The Kit:

Chains:

We offer customers a choice between genuine Nissan and German Iwis chains. Iwis chains cannot be used with genuine or aftermarket sprockets (other than ours) due to differences in pitch and width. We supply Australian made sprockets manufactured to suit the pitch and width of each chain. The Iwis chain we offer is used in many European high performance vehicles. For example, a 60 link Iwis chain, with its highly polished low friction link plates, is used as an upgrade for the primary timing chain for the Lamborghini Murcielago SV. Our fuel pump drive chain is a 94 link version of the one used for the Lamborghini.

Before deciding which chains to supply with this kit, extensive testing of the German Iwis chain and aftermarket fuel pump chains was undertaken. There was no need to test the genuine Nissan chain. Each chain was subjected to in vehicle testing comprising 400 hours engine running time. The results showed that the aftermarket chains (all of which had harder pins than the Iwis chain) had wear to the pins and bushings ranging from 3.0mm to 4.5mm while the Iwis chain had the least wear at 0.5mm. These results do not support claims that harder pins lead to longer chain life. Aftermarket chains are easily identified by plain packaging and the absence of manufacturer stamp, name or logo.

Sprockets:

Some aftermarket sprockets do not correctly mesh with a genuine Nissan chain. The poor fitting chain wrap on the aftermarket sprockets will cause rapid chain wear and imminent chain failure. The "Yd25.com.au" brand sprockets fit perfectly thus guaranteeing maximum chain and sprocket life.

Original factory YD25 crankshaft and vacuum pump sprockets and some of the aftermarket sprockets that we know of are made from SMF4040 carbon steel. The process of manufacture is powder metallurgy sintered metal. The later YD25 engines with common rail injection require higher fuel pressures which places the crankshaft sprocket under higher loads than earlier engines. Higher loads mean more wear to carbon steel sprockets. To handle these higher loads, the crankshaft sprocket is manufactured from billet 4340 high tensile steel and the vacuum pump sprocket from billet 4140 high tensile steel. Both sprockets are nitride hardened. While carbon steel sprockets can be manufactured for a fraction of the cost of a fully machined high tensile steel sprocket, our aim is to provide a high quality sprocket backed by a five year, 100,000km warranty. The Brisbane based sprocket manufacturer has over 50 years experience in sprocket design and manufacture. Every YD25 sprocket is subject to a stringent quality assurance process before leaving the factory.

Upgrading To Duplex:

Our timing chain kit is a conversion kit. All competitors kits are modification kits.

Conversion Kit:

With our kit, to convert the vac pump to duplex, simply remove the single row sprocket and replace it with our duplex sprocket. It is that simple.

Modification Kit:

The process is not that simple with competitors modification kit. The vacuum pump is fitted with modified internal parts. To achieve this most workshops go through the following steps.

Removal of the engine from the car.
Remove the fuel pump from the engine.
Remove the vacuum pump from the engine.
Dis-assemble the vacuum pump.
Fit modified vacuum pump shaft to the vacuum pump housing.
Assemble the vacuum pump.
Fit duplex sprocket to the vacuum pump shaft.
Refit the vacuum pump to the engine.
Refit the fuel pump to the engine.
Due to the limited space in which to remove the fuel pump and vacuum pump with the engine in the car, the engine is usually removed when fitting a modification kit. Owners need to be aware that fitting a modification kit the vacuum pump and fuel pump sealing surfaces are disturbed with the potential for ingress of grit on the o-ring seals which significantly increases the potential for oil leaks. Dis-assembly of the vacuum pump can also damage internal components and casing (which are a non-serviceable items) requiring a complete pump replacement.

Tensioners:

This kit includes genuine Japanese Tsubaki tensioners in their original Nissan packaging. These are the best available. The top tensioner is supplied with an additional fail safe component. When new chains and guides are fitted, the fail safe component only allows the tensioner to back off 1.0mm. Without the fail safe, the tensioner can back off 7.0 to 8.0 mm which, when combined with 3.0 to 4.0mm of wear to the chain, can result in the chain jumping teeth. We have found aftermarket tensioners to have high valve failure rates. These tensioners come in plastic bags or white boxes with no manufacturer stamp, name or logo. Failed aftermarket tensioners have cost some owners their engine.

Special Tools:

A scissor gear tool is included in each kit to assist installers to maintain the pretension between the scissor gear and the idler gear during removal and installation. Failure to maintain the pretension and timing will cause vibrations putting undue stress on the engine internal components.

Contents:

• 1 X Duplex fuel pump sprocket
• 1 X Duplex crankshaft sprocket (Australian made)
• 1 X Duplex vacuum pump sprocket (Australian made)
• 1 X Duplex fuel pump drive chain (genuine Nissan Japan or Iwis Germany)
• 1 X Duplex camshaft drive chain (genuine Nissan)
• 1 X Cam chain tensioner (genuine Nissan, plus an Australian made fail-safe component)
• 1 X Fuel pump chain tensioner (genuine Nissan)
• 1 X Crankshaft oil seal
• 1 X Scissor gear tool (Australian made)
• 1 X Oil pump o-ring set
• 7 X Quality chain guide

Vehicle Fitment Guide

Parts Guide

Please select the part number you require from the variation by utilising our vehicle fitment guide and parts guide.

Notes:

• This timing chain kit does not suit 140kW models. Please check your vehicle before purchasing if you are unsure, or contact us for assistance.
• We offer a five year, 100,000km chain and sprocket warranty. This is five times the industry standard. Evidence that the vehicle has been serviced according to Nissan guidelines will be required to support a warranty claim. The warranty covers premature wear to chains and sprockets. Damage as a result of incorrect installation by anyone apart from us, other parts failing causing chain and sprocket damage or continuing to drive the vehicle when there is an unusual noise coming from the motor rather than having it repaired will not be covered by our warranty.
• All other timing chain components are covered by a 12months/20,000kms warranty.