Gearing up to do head gaskets on an '03 4.6. Gaskets do not leak at the moment (168 K on the motor) but customer wants the job done before they move to northern British Columbia. (I would rather not touch this repair... but the owners feel the "peace of mind" is worth the expense. Looking to purchase valve seat cutters. Neway has a kit they've assembled for Land Rover, and they include 20, 46 and 70 degree cutters. (And pilots with a 8.73 and 8.76 millimeter diameter.) It's the 46 degree angle cutter that I'm wondering about. Does LR do theirs that way, compared to the conventional 45 degrees?

 

To do a single set of heads, I'd just hand lap them or send them to a machine shop for a valve job.

For someone looking to do the work for future reliability, I'd stick with a single angle valve job. Very rare to have an issue with the thinner seat on a 3 angle job, but it does occasionally happen.

As for the diameters, don't have the specs off hand but they are out there searchable. Someone else may pop in and be able to help more.

 

It's called interference angle. They are off by 1 degree, this helps increase the sealing force of the two surfaces. If I remember correctly.

My valve cutter set is intended for small engines, luckily the Rover 4.0 and 4.6 have small valves, the 46 isn't LR specific.

 

As I understand it, Neway has a good reputation.... their catalogue has an array of 45 degree cutters, but very few 46 degree. As suggested by Alex_M, and hand lap may be quite sufficient. But I'm thinking if I opt for purchasing a cutter, the 46 degree one is the right way to go. Thanks for your replies!

 

IMO, if the customer wants peace of mind you should sell them the inline thermostat kit and replace any other suspect components such as cooling system hoses, coolant bottle/cap, and the radiator; I wouldn't touch HGs that aren't leaking before a big trip.

 

this morning I spoke with the customers, and told them to sign on to this forum. Just to get acquainted. Now I'm going to check on whether they noticed this thread, and your reply gecko951. I completely agree with your suggestions! (Thank you for them.)