Jump to content
SAU Community

Recommended Posts

Posted (edited)

I just replaced the timing belt, along with tensioner, idler, water pump, etc. all the front end engine stuff with all new stock Nissan parts on my 98 R34 GTT that I just recently got, so glad I did as the belt ,tensor, idler and water pump were all original to the car with over 161 Km and looked absolutely terrible, honestly I cant believe the belt has not broken, luckily I have not driving the vehicle since I got it, and only have ran a few times because I've been restoring it over this winter. I turned engine over by hand and lined up all the timing marks from cams, to the head (plate behind pulleys), and crank to  oil pump block mark, as ran fine, but had a lot of front end noise. the idler sounded like gravel and the tensioner had to no tensor left on it at all as it appeared the spring had rusted in place due to a waterpump leak over the years. so the timing belt was very loose on the left or tensioner side.

Never the less I turn engine by hand until everything lined up even with the marks on the original belt. I remove everything making sure not to rotate anything, then put in new tensioner,  idler, made sure all marks from belt matched marks on the pulleys, cams and crank alike and all marks from crank and cams to head and block were perfect. I slowly turned by hand and everything lined up on the cams and crank to the head and block every other time, as proper. all looked fine until I put the lower timing belt cover back on, then the  harmonic balancer, at this point before torqueing the crank bolt down I noticed the timing mark on the lower cover to the harmonic balancer is off.

I think the marks on the harmonic balancer and in 5 degrees, from 0-20  and it should be at 0, but some how its around -2.5, not enough for a belt notch, and there is little play in this cover to the block.

The key way and key are perfect on the crank and slot in balancer is perfect, no play here, and the cams and other timing marks seem to be on. Is this something to be concerned with or will it be fine. maybe just this way due to a new stock Nissan belt?? slightly tight and will stretch a hair???

I marked the CAS before disassembly and know it should be set to 15 degrees BTDC or so at 650 rpms per engine decal. so do I need to worry about what appears to be a slight retard of the mechanical timing? or will this slight difference be compensated when I adjust my CAS?

 

appreciate any insight.

 

 

Edited by JC71
Link to comment
https://www.sau.com.au/forums/topic/485483-rb25det-neo-r34-timing-belt/
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Update for the sake of closure   Ended up getting the intercooler piping all sorted, new plugs and yellow jacket coils, and she was idling mint until it warmed up while I was bleeding the cooling system. Found the misfire to be localised to cyl 3 by unplugging coilpacks, ran a compression test, that checked out, then decided to get a mate to check if that spark plug was firing out of the motor. Upon cranking it over, with the injectors disconnected, the car actually fired and ran on a couple cylinders and heaps of fuel came out the top of cyl 3 I'd say that injector's either spraying incorrectly or spraying far too much, which is fine as I'm planning on replacing them anyway I'm planning on making about 250kW on flex fuel, and have a set of 1000cc injectors from ozautosport, obviously overkill but I'm planning on building the motor and running more boost further down the line, do you reckon they'd be too big for a smooth idle on 98? Thanks for the replies gents, much appreciated
    • I'm confused. You said you want to "remove the clear coat from most panels" but it sounds like you are actually doing a full respray? Few random things to add -  If you chase the blistered paint with 120 grit, I can almost guarantee you'll chase it down to bare metal (that's fine). But if you paint the car from here, you'll have nice little indents where ever the blistered paint was. The new paint won't magically level out the low areas, you need to fill them. Which leads me to the main point I wanted to add, make sure the whole car is flat before you paint it. All those areas with blistered paint you sanded out, make sure to fill them and triple check they are flat with a block guide coat. I'd also check the whole car is flat with a large block and guide coat but yeah up to you if you want to go that far.   
    • 300hp (225kw) is barely outside the standard turbo's range with a bit of extra boost in it (200ish). If you are going to change the turbo you should aim for 250-300kw (330-400hp) to make the expense worthwhile
    • A couple of things, firstly omg that turbo is expensive! $3,000 USD for dinosaur technology is robbery. You could buy a G series turbo and have a good amount of change instead.  If you want a good budget option, have a look here - https://hypergearturbos.com/product/rb25dethighflow/ If you are keen to spend more, have look at the modern turbos, Garrett G series, Borgwarner EFR, etc. Have a look at the RB25 dyno results thread for inspiration.  If you upgrade your turbo to something that will support the 300hp you want and only "probably" have Haltech ECU, your car will only "probably" run. Actually, no it won't run. You are going to need the ECU and injectors at the time you do the turbo upgrade.  No thoughts on "this much boost" as you didn't say how much boost that actually is. Having said that, plenty of unopened RB25's making even more power then what you are chasing.   
×
×
  • Create New...