Date: Sun, 7 May 1995 22:05:16 -0500 From: rover@pinn.net (Alexander P. Grice)
Working at a Land Rover dealership, I saw more than my share of Land-Rovers new and old come in for tests. I cut what slack the system allowed (which wasn't much since it was all computerized), especially on the old ones. Here's what I learned:
1) Most programs want factory spec engines. In theory, that means a Zenith or a Solex in their proper places, factory manifolds and PCV valves. With old Land-Rovers, most smog techs won't know the difference between a Zenith or a Weber 1 barrel, a diaphragm PCV from a spring-and-piston. They will draw the line, usually, with a header or a 2 bbl.
Many of the factory emission parts, like the EGR setup on Series IIIs are long out of production. If the tech turns up some obscure bit of paper showing that a '73 88 should have an EGR valve, it's easy to prove that these parts are unavailable. In California, it meant a trip to a referee station with a list of out-of-production parts from a Land Rover dealer as proof to get an exemption. [See the list at the end.]
2) If I remember correctly, the last CO/HC limits for an older Land- Rover before I left were 2% carbon monoxide and 150 ppm hydrocarbons. You could make them run on those settings with difficulty. The factory emission tag on a '69, for example, asks for a 6% CO adjustment. The HC reading at 6% was about 300 PPM, and adjusting the CO to 2% sometimes made the HC rise. The test called for the timing to be set to factory spec and because the computer couldn't tell where it was set, I often retarded it to get the HC to come down.
If your timing has to be checked by the tech as a part of the test, make sure it's set to the lowest number you can document in the literature for your Landy. Set it at the "pee-water" P-Mex fuel setting of 3 or 6 degrees ATDC. As Kelly Minnick said, a good tuneup, an oil change and gasohol or oxygenated fuel in the tank will also make the test go smoother. The idle number should also be set on the highest number in the specs. That also helps keep the HC down.
3) California had a limit on repairs if your car couldn't pass the test. I believe it was $300. If your vehicle had all the proper equipment and still couldn't be made to pass (after letting the tech fool around to the tune of $300), you went to the referee station and got a certificate. This did not apply to modified engines or missing emission components. Tired engines did qualify for the exemptions.
4) Don't go in for a test if your exhaust system has leaks. The test equipment in California could sense exhaust leaks and abort the test.
5) Finding a sympathetic tech is helpful. Don't offer bribes, but remember that he can cut you a lot of slack if so inclined. If the shop is one you normally use (assuming the test station is not state-run), your odds are better. Good luck!
Land Rover/Unipart Smog Equipment No Longer Available
574244 Zenith 36IVE carb, fitted to engine #30600001 on. 587128 Zenith 36IVE carb, fitted to engine #30700001 Suffix "A" on. 587521 Zenith 36IVE carb, fitted to engine #30600001 Suffix "B" on. 542410 Emission valve (PCV breather). 596384 Diaphragm unit, Series III. 596385 Trigger Valve, Series III. 574933 Distributor, IIa, Engine #30600001 on. 574245 Distributor, IIa, Engine #30700001 on. 587497 Distributor, IIa, Engine #30700001 Suffix "B" on. 578065 Breather Canister, IIa Frame #24439373G on & all Series III. 041866 EGR Valve assembly.
*----"Jeep may be famous, LAND-ROVER is Legendary"----*
| A. P. (Sandy) Grice |
| Rover Owners' Association of Virginia |
| 1633 Melrose Parkway, Norfolk, VA 23508-1730 |
| E-mail: rover@pinn.net Phone: 804-622-7054 (Day) |
| 804-423-4898 (Evenings) FAX: 804-622-7056 |
*-----------------------------------------------------*
From: "David McKain" (MCKAIN@faculty.coe.wvu.edu) Date: Tue, 30 May 1995 13:58:21 EDT Subject: Emissions
This is just the start of a trial FAQ type document on emissions production and control. The information it contains will be based on internal combustion engine reference books and recommendations from experienced emissions test personnel. Please feel free to provide feedback both positive and negative.
Effect of Fuel/Air ratio on basic emissions :
One of the most important variables in determining engine emissions
is fuel/air ratio. Normally, and engine operates at close to
stochiometric conditions, that is, with a fuel/air ratio close to 1.
Leaner mixtures will generally give lower emissions but may result in
poor engine operation. During start up, when the engine is cold, fuel
enrichment is normally used which results in an increase in Carbon
Monoxide (CO) and Hydrocarbons (HC) and a decrease in Oxides of
Nitrogen (NOX). As the engine warms up and enrichment is reduced, CO
and HC will be reduced while NOX will increase. At part-load
conditions, lean mixtures can be used to lower CO, HC, and NOX
emissions, at least until combustion quality and thus engine
performance deteriorate. One method of reducing NOX emissions is the
use of Exhaust Gas Recirculation (EGR) where a portion of the exhaust
is feed back into the intake of the engine but this will also result
in a deterioration of engine performance.
Spark Timing:
Spark timing can significantly affect NOX emissions. Advancing the
timing so that combustion occurrs earlier in the cycle increases the
peak cyclinder pressure. This will result in higher peak cylinder
temperatures and thus an increase in NOX formation.
As I said, this is just a start. I am still gathering information and would appreciate any on emissions formation, emissions regulation (US, UK) and experiences with DOT and MOT inspection stations (especially ways to self regulate emissions in order to pass inspection). Please e-mail direct. This document will also include diesel engine information.
David McKain 1966 SIIa Petrol mckain@faculty.coe.wvu.edu (304) 599-0120 Morgantown, WV, USA